Initial commit

application/Espo/ORM/Collection.php

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+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM;
+
+use Traversable;
+use stdClass;
+
+/**
+ * A collection of entities.
+ *
+ * @template-covariant TEntity of Entity
+ * @extends Traversable<int, TEntity>
+ */
+interface Collection extends Traversable
+{
+    /**
+     * Get an array of stdClass objects.
+     *
+     * @return stdClass[]
+     */
+    public function getValueMapList(): array;
+}

application/Espo/ORM/CollectionFactory.php

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+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM;
+
+use Espo\ORM\Query\Select;
+
+/**
+ * Creates collections.
+ */
+class CollectionFactory
+{
+    public function __construct(protected EntityManager $entityManager)
+    {}
+
+    /**
+     * Create.
+     *
+     * @param array<Entity|array<string, mixed>> $dataList
+     * @return EntityCollection<Entity>
+     */
+    public function create(?string $entityType = null, array $dataList = []): EntityCollection
+    {
+        return new EntityCollection($dataList, $entityType, $this->entityManager->getEntityFactory());
+    }
+
+    /**
+     * Create from an SQL.
+     *
+     * @return SthCollection<Entity>
+     */
+    public function createFromSql(string $entityType, string $sql): SthCollection
+    {
+        return SthCollection::fromSql($entityType, $sql, $this->entityManager);
+    }
+
+    /**
+     * Create from a query.
+     *
+     * @return SthCollection<Entity>
+     */
+    public function createFromQuery(Select $query): SthCollection
+    {
+        return SthCollection::fromQuery($query, $this->entityManager);
+    }
+
+    /**
+     * Create EntityCollection from SthCollection.
+     *
+     * @template TEntity of Entity
+     * @param SthCollection<TEntity> $sthCollection
+     * @return EntityCollection<TEntity>
+     */
+    public function createFromSthCollection(SthCollection $sthCollection): EntityCollection
+    {
+        /** @var EntityCollection<TEntity> */
+        return EntityCollection::fromSthCollection($sthCollection);
+    }
+}

application/Espo/ORM/DB/Query/Base.php

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+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\DB\Query;
+
+/**
+ * @deprecated As of v6.0. Not to be used directly.
+ */
+abstract class Base extends \Espo\ORM\QueryComposer\BaseQueryComposer
+{
+
+}

application/Espo/ORM/DataLoader/EmptyLoader.php

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+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\DataLoader;
+
+use Espo\ORM\Entity;
+
+class EmptyLoader implements Loader
+{
+    public function load(Entity $entity): void
+    {}
+}

application/Espo/ORM/DataLoader/Loader.php

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+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\DataLoader;
+
+use Espo\ORM\Entity;
+
+interface Loader
+{
+    public function load(Entity $entity): void;
+}

application/Espo/ORM/DataLoader/RDBLoader.php

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+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\DataLoader;
+
+use Espo\ORM\Entity;
+use Espo\ORM\EntityManager;
+
+class RDBLoader implements Loader
+{
+    public function __construct(
+        private EntityManager $entityManager,
+    ) {}
+
+    public function load(Entity $entity): void
+    {
+        $loaded = $this->entityManager->getEntityById($entity->getEntityType(), $entity->getId());
+
+        if (!$loaded) {
+            return;
+        }
+
+        foreach ($loaded->getAttributeList() as $attribute) {
+            if (!$loaded->has($attribute)) {
+                continue;
+            }
+
+            $value = $loaded->get($attribute);
+
+            if (!$entity->hasFetched($attribute)) {
+                $entity->setFetched($attribute, $value);
+            }
+
+            if (!$entity->has($attribute)) {
+                $entity->set($attribute, $value);
+            }
+        }
+    }
+}

application/Espo/ORM/DatabaseParams.php

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+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM;
+
+use SensitiveParameter;
+
+/**
+ * Immutable.
+ */
+class DatabaseParams
+{
+    private ?string $platform = null;
+    private ?string $host = null;
+    private ?int $port = null;
+    private ?string $name = null;
+    private ?string $username = null;
+    private ?string $password = null;
+    private ?string $charset = null;
+    private ?string $sslCa = null;
+    private ?string $sslCert = null;
+    private ?string $sslKey = null;
+    private ?string $sslCaPath = null;
+    private ?string $sslCipher = null;
+    private bool $sslVerifyDisabled = false;
+
+    public static function create(): self
+    {
+        return new self();
+    }
+
+    public function getPlatform(): ?string
+    {
+        return $this->platform;
+    }
+
+    public function getHost(): ?string
+    {
+        return $this->host;
+    }
+
+    public function getPort(): ?int
+    {
+        return $this->port;
+    }
+
+    public function getName(): ?string
+    {
+        return $this->name;
+    }
+
+    public function getUsername(): ?string
+    {
+        return $this->username;
+    }
+
+    public function getPassword(): ?string
+    {
+        return $this->password;
+    }
+
+    public function getCharset(): ?string
+    {
+        return $this->charset;
+    }
+
+    public function getSslCa(): ?string
+    {
+        return $this->sslCa;
+    }
+
+    public function getSslCert(): ?string
+    {
+        return $this->sslCert;
+    }
+
+    public function getSslCaPath(): ?string
+    {
+        return $this->sslCaPath;
+    }
+
+    public function getSslCipher(): ?string
+    {
+        return $this->sslCipher;
+    }
+
+    public function getSslKey(): ?string
+    {
+        return $this->sslKey;
+    }
+
+    public function isSslVerifyDisabled(): bool
+    {
+        return $this->sslVerifyDisabled;
+    }
+
+    public function withPlatform(?string $platform): self
+    {
+        $obj = clone $this;
+        $obj->platform = $platform;
+
+        return $obj;
+    }
+
+    public function withHost(?string $host): self
+    {
+        $obj = clone $this;
+        $obj->host = $host;
+
+        return $obj;
+    }
+
+    public function withPort(?int $port): self
+    {
+        $obj = clone $this;
+        $obj->port = $port;
+
+        return $obj;
+    }
+
+    public function withName(?string $name): self
+    {
+        $obj = clone $this;
+        $obj->name = $name;
+
+        return $obj;
+    }
+
+    public function withUsername(?string $username): self
+    {
+        $obj = clone $this;
+        $obj->username = $username;
+
+        return $obj;
+    }
+
+    public function withPassword(#[SensitiveParameter] ?string $password): self
+    {
+        $obj = clone $this;
+        $obj->password = $password;
+
+        return $obj;
+    }
+
+    public function withCharset(?string $charset): self
+    {
+        $obj = clone $this;
+        $obj->charset = $charset;
+
+        return $obj;
+    }
+
+    public function withSslCa(?string $sslCa): self
+    {
+        $obj = clone $this;
+        $obj->sslCa = $sslCa;
+
+        return $obj;
+    }
+
+    public function withSslCaPath(?string $sslCaPath): self
+    {
+        $obj = clone $this;
+        $obj->sslCaPath = $sslCaPath;
+
+        return $obj;
+    }
+
+    public function withSslCert(?string $sslCert): self
+    {
+        $obj = clone $this;
+        $obj->sslCert = $sslCert;
+
+        return $obj;
+    }
+
+    public function withSslCipher(?string $sslCipher): self
+    {
+        $obj = clone $this;
+        $obj->sslCipher = $sslCipher;
+
+        return $obj;
+    }
+
+    public function withSslKey(?string $sslKey): self
+    {
+        $obj = clone $this;
+        $obj->sslKey = $sslKey;
+
+        return $obj;
+    }
+
+    public function withSslVerifyDisabled(bool $sslVerifyDisabled = true): self
+    {
+        $obj = clone $this;
+        $obj->sslVerifyDisabled = $sslVerifyDisabled;
+
+        return $obj;
+    }
+}

application/Espo/ORM/Defs.php

@@ -0,0 +1,36 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM;
+
+/**
+ * Definitions.
+ */
+class Defs extends Defs\Defs
+{}

application/Espo/ORM/Defs/AttributeDefs.php

@@ -0,0 +1,115 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Defs;
+
+use Espo\ORM\Defs\Params\AttributeParam;
+
+/**
+ * Attribute definitions.
+ */
+class AttributeDefs
+{
+    /** @var array<string, mixed> */
+    private array $data;
+    private string $name;
+
+    private function __construct()
+    {}
+
+    /**
+     * @param array<string, mixed> $raw
+     */
+    public static function fromRaw(array $raw, string $name): self
+    {
+        $obj = new self();
+        $obj->data = $raw;
+        $obj->name = $name;
+
+        return $obj;
+    }
+
+    /**
+     * Get a name.
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * Get a type.
+     */
+    public function getType(): string
+    {
+        return $this->data[AttributeParam::TYPE];
+    }
+
+    /**
+     * Get a length.
+     */
+    public function getLength(): ?int
+    {
+        return $this->data[AttributeParam::LEN] ?? null;
+    }
+
+    /**
+     * Whether is not-storable. Not-storable attributes are not stored in DB.
+     */
+    public function isNotStorable(): bool
+    {
+        return $this->data[AttributeParam::NOT_STORABLE] ?? false;
+    }
+
+    /**
+     * Whether is auto-increment.
+     */
+    public function isAutoincrement(): bool
+    {
+        return $this->data[AttributeParam::AUTOINCREMENT] ?? false;
+    }
+
+    /**
+     * Whether a parameter is set.
+     */
+    public function hasParam(string $name): bool
+    {
+        return array_key_exists($name, $this->data);
+    }
+
+    /**
+     * Get a parameter value by a name.
+     *
+     * @return mixed
+     */
+    public function getParam(string $name)
+    {
+        return $this->data[$name] ?? null;
+    }
+}

application/Espo/ORM/Defs/Defs.php

@@ -0,0 +1,99 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Defs;
+
+use RuntimeException;
+
+/**
+ * Definitions.
+ */
+class Defs
+{
+    public function __construct(private DefsData $data)
+    {}
+
+    /**
+     * Get an entity type list.
+     *
+     * @return string[]
+     */
+    public function getEntityTypeList(): array
+    {
+        return $this->data->getEntityTypeList();
+    }
+
+    /**
+     * Get an entity definitions list.
+     *
+     * @return EntityDefs[]
+     */
+    public function getEntityList(): array
+    {
+        $list = [];
+
+        foreach ($this->getEntityTypeList() as $name) {
+            $list[] = $this->getEntity($name);
+        }
+
+        return $list;
+    }
+
+    /**
+     * Has an entity type.
+     */
+    public function hasEntity(string $entityType): bool
+    {
+        return $this->data->hasEntity($entityType);
+    }
+
+    /**
+     * Get entity definitions.
+     */
+    public function getEntity(string $entityType): EntityDefs
+    {
+        if (!$this->hasEntity($entityType)) {
+            throw new RuntimeException("Entity type '{$entityType}' does not exist.");
+        }
+
+        return $this->data->getEntity($entityType);
+    }
+
+    /**
+     * Try to get entity definitions, if an entity type does not exist, then return null.
+     */
+    public function tryGetEntity(string $entityType): ?EntityDefs
+    {
+        if (!$this->hasEntity($entityType)) {
+            return null;
+        }
+
+        return $this->getEntity($entityType);
+    }
+}

application/Espo/ORM/Defs/DefsData.php

@@ -0,0 +1,95 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Defs;
+
+use Espo\ORM\Metadata;
+
+use RuntimeException;
+
+class DefsData
+{
+    /** @var array<string, ?EntityDefs> */
+    private array $cache = [];
+
+    public function __construct(private Metadata $metadata)
+    {}
+
+    public function clearCache(): void
+    {
+        $this->cache = [];
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getEntityTypeList(): array
+    {
+        return $this->metadata->getEntityTypeList();
+    }
+
+    public function hasEntity(string $name): bool
+    {
+        $this->cacheEntity($name);
+
+        return !is_null($this->cache[$name]);
+    }
+
+    public function getEntity(string $name): EntityDefs
+    {
+        $this->cacheEntity($name);
+
+        if (!$this->hasEntity($name)) {
+            throw new RuntimeException("Entity type '{$name}' does not exist.");
+        }
+
+        /** @var EntityDefs */
+        return $this->cache[$name];
+    }
+
+    private function cacheEntity(string $name): void
+    {
+        if (array_key_exists($name, $this->cache)) {
+            return;
+        }
+
+        $this->cache[$name] = $this->loadEntity($name);
+    }
+
+    private function loadEntity(string $name): ?EntityDefs
+    {
+        $raw = $this->metadata->get($name) ?? null;
+
+        if (!$raw) {
+            return null;
+        }
+
+        return EntityDefs::fromRaw($raw, $name);
+    }
+}

application/Espo/ORM/Defs/EntityDefs.php

@@ -0,0 +1,431 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Defs;
+
+use Espo\ORM\Defs\Params\EntityParam;
+use RuntimeException;
+
+class EntityDefs
+{
+    /** @var array<string, array<string, mixed>|mixed> */
+    private array $data;
+    private string $name;
+    /** @var array<string, ?AttributeDefs> */
+    private $attributeCache = [];
+    /** @var array<string, ?RelationDefs> */
+    private $relationCache = [];
+    /** @var array<string, ?IndexDefs> */
+    private $indexCache = [];
+    /** @var array<string, ?FieldDefs> */
+    private $fieldCache = [];
+
+    private function __construct()
+    {}
+
+    /**
+     * @param array<string, mixed> $raw
+     */
+    public static function fromRaw(array $raw, string $name): self
+    {
+        $obj = new self();
+        $obj->data = $raw;
+        $obj->name = $name;
+
+        return $obj;
+    }
+
+    /**
+     * Get an entity name (entity type).
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * Get an attribute name list.
+     *
+     * @return string[]
+     */
+    public function getAttributeNameList(): array
+    {
+        /** @var string[] */
+        return array_keys($this->data[EntityParam::ATTRIBUTES] ?? []);
+    }
+
+    /**
+     * Get a relation name list.
+     *
+     * @return string[]
+     */
+    public function getRelationNameList(): array
+    {
+        /** @var string[] */
+        return array_keys($this->data[EntityParam::RELATIONS] ?? []);
+    }
+
+    /**
+     * Get an index name list.
+     *
+     * @return string[]
+     */
+    public function getIndexNameList(): array
+    {
+        /** @var string[] */
+        return array_keys($this->data[EntityParam::INDEXES] ?? []);
+    }
+
+    /**
+     * Get a field name list.
+     *
+     * @return string[]
+     */
+    public function getFieldNameList(): array
+    {
+        /** @var string[] */
+        return array_keys($this->data[EntityParam::FIELDS] ?? []);
+    }
+
+    /**
+     * Get an attribute definitions list.
+     *
+     * @return AttributeDefs[]
+     */
+    public function getAttributeList(): array
+    {
+        $list = [];
+
+        foreach ($this->getAttributeNameList() as $name) {
+            $list[] = $this->getAttribute($name);
+        }
+
+        return $list;
+    }
+
+    /**
+     * Get a relation definitions list.
+     *
+     * @return RelationDefs[]
+     */
+    public function getRelationList(): array
+    {
+        $list = [];
+
+        foreach ($this->getRelationNameList() as $name) {
+            $list[] = $this->getRelation($name);
+        }
+
+        return $list;
+    }
+
+    /**
+     * Get an index definitions list.
+     *
+     * @return IndexDefs[]
+     */
+    public function getIndexList(): array
+    {
+        $list = [];
+
+        foreach ($this->getIndexNameList() as $name) {
+            $list[] = $this->getIndex($name);
+        }
+
+        return $list;
+    }
+
+    /**
+     * Get a field definitions list.
+     *
+     * @return FieldDefs[]
+     */
+    public function getFieldList(): array
+    {
+        $list = [];
+
+        foreach ($this->getFieldNameList() as $name) {
+            $list[] = $this->getField($name);
+        }
+
+        return $list;
+    }
+
+    /**
+     * Has an attribute.
+     */
+    public function hasAttribute(string $name): bool
+    {
+        $this->cacheAttribute($name);
+
+        return !is_null($this->attributeCache[$name]);
+    }
+
+    /**
+     * Has a relation.
+     */
+    public function hasRelation(string $name): bool
+    {
+        $this->cacheRelation($name);
+
+        return !is_null($this->relationCache[$name]);
+    }
+
+    /**
+     * Has an index.
+     */
+    public function hasIndex(string $name): bool
+    {
+        $this->cacheIndex($name);
+
+        return !is_null($this->indexCache[$name]);
+    }
+
+    /**
+     * Has a field.
+     */
+    public function hasField(string $name): bool
+    {
+        $this->cacheField($name);
+
+        return !is_null($this->fieldCache[$name]);
+    }
+
+    /**
+     * Get attribute definitions.
+     *
+     * @throws RuntimeException
+     */
+    public function getAttribute(string $name): AttributeDefs
+    {
+        $this->cacheAttribute($name);
+
+        if (!$this->hasAttribute($name)) {
+            throw new RuntimeException("Attribute '{$name}' does not exist.");
+        }
+
+        /** @var AttributeDefs */
+        return $this->attributeCache[$name];
+    }
+
+    /**
+     * Get relation definitions.
+     *
+     * @throws RuntimeException
+     */
+    public function getRelation(string $name): RelationDefs
+    {
+        $this->cacheRelation($name);
+
+        if (!$this->hasRelation($name)) {
+            throw new RuntimeException("Relation '{$name}' does not exist.");
+        }
+
+        /** @var RelationDefs */
+        return $this->relationCache[$name];
+    }
+
+    /**
+     * Get index definitions.
+     *
+     * @throws RuntimeException
+     */
+    public function getIndex(string $name): IndexDefs
+    {
+        $this->cacheIndex($name);
+
+        if (!$this->hasIndex($name)) {
+            throw new RuntimeException("Index '{$name}' does not exist.");
+        }
+
+        /** @var IndexDefs */
+        return $this->indexCache[$name];
+    }
+
+    /**
+     * Get field definitions.
+     *
+     * @throws RuntimeException
+     */
+    public function getField(string $name): FieldDefs
+    {
+        $this->cacheField($name);
+
+        if (!$this->hasField($name)) {
+            throw new RuntimeException("Field '{$name}' does not exist.");
+        }
+
+        /** @var FieldDefs */
+        return $this->fieldCache[$name];
+    }
+
+    /**
+     * Try to get attribute definitions.
+     */
+    public function tryGetAttribute(string $name): ?AttributeDefs
+    {
+        if (!$this->hasAttribute($name)) {
+            return null;
+        }
+
+        return $this->getAttribute($name);
+    }
+
+    /**
+     * Try to get field definitions.
+     */
+    public function tryGetField(string $name): ?FieldDefs
+    {
+        if (!$this->hasField($name)) {
+            return null;
+        }
+
+        return $this->getField($name);
+    }
+
+    /**
+     * Try to get relation definitions.
+     */
+    public function tryGetRelation(string $name): ?RelationDefs
+    {
+        if (!$this->hasRelation($name)) {
+            return null;
+        }
+
+        return $this->getRelation($name);
+    }
+
+    /**
+     * Try to get index definitions.
+     */
+    public function tryGetIndex(string $name): ?IndexDefs
+    {
+        if (!$this->hasIndex($name)) {
+            return null;
+        }
+
+        return $this->getIndex($name);
+    }
+
+    /**
+     * Whether a parameter is set.
+     */
+    public function hasParam(string $name): bool
+    {
+        return array_key_exists($name, $this->data);
+    }
+
+    /**
+     * Get a parameter value by a name.
+     */
+    public function getParam(string $name): mixed
+    {
+        return $this->data[$name] ?? null;
+    }
+
+    private function cacheAttribute(string $name): void
+    {
+        if (array_key_exists($name, $this->attributeCache)) {
+            return;
+        }
+
+        $this->attributeCache[$name] = $this->loadAttribute($name);
+    }
+
+    private function loadAttribute(string $name): ?AttributeDefs
+    {
+        $raw = $this->data[EntityParam::ATTRIBUTES][$name] ?? null;
+
+        if (!$raw) {
+            return null;
+        }
+
+        return AttributeDefs::fromRaw($raw, $name);
+    }
+
+    private function cacheRelation(string $name): void
+    {
+        if (array_key_exists($name, $this->relationCache)) {
+            return;
+        }
+
+        $this->relationCache[$name] = $this->loadRelation($name);
+    }
+
+    private function loadRelation(string $name): ?RelationDefs
+    {
+        $raw = $this->data[EntityParam::RELATIONS][$name] ?? null;
+
+        if (!$raw) {
+            return null;
+        }
+
+        return RelationDefs::fromRaw($raw, $name);
+    }
+
+    private function cacheIndex(string $name): void
+    {
+        if (array_key_exists($name, $this->indexCache)) {
+            return;
+        }
+
+        $this->indexCache[$name] = $this->loadIndex($name);
+    }
+
+    private function loadIndex(string $name): ?IndexDefs
+    {
+        $raw = $this->data[EntityParam::INDEXES][$name] ?? null;
+
+        if (!$raw) {
+            return null;
+        }
+
+        return IndexDefs::fromRaw($raw, $name);
+    }
+
+    private function cacheField(string $name): void
+    {
+        if (array_key_exists($name, $this->fieldCache)) {
+            return;
+        }
+
+        $this->fieldCache[$name] = $this->loadField($name);
+    }
+
+    private function loadField(string $name): ?FieldDefs
+    {
+        $raw = $this->data[EntityParam::FIELDS][$name] ?? null;
+
+        if (!$raw) {
+            return null;
+        }
+
+        return FieldDefs::fromRaw($raw, $name);
+    }
+}

application/Espo/ORM/Defs/FieldDefs.php

@@ -0,0 +1,104 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Defs;
+
+use Espo\ORM\Defs\Params\FieldParam;
+use RuntimeException;
+
+/**
+ * Field definitions.
+ */
+class FieldDefs
+{
+    /** @var array<string, mixed> */
+    private array $data;
+    private string $name;
+
+    private function __construct()
+    {}
+
+    /**
+     * @param array<string, mixed> $raw
+     */
+    public static function fromRaw(array $raw, string $name): self
+    {
+        $obj = new self();
+        $obj->data = $raw;
+        $obj->name = $name;
+
+        return $obj;
+    }
+
+    /**
+     * Get a name.
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * Get a type.
+     */
+    public function getType(): string
+    {
+        $type = $this->data[FieldParam::TYPE] ?? null;
+
+        if ($type === null) {
+            throw new RuntimeException("Field '$this->name' has no type.");
+        }
+
+        return $type;
+    }
+
+    /**
+     * Whether is not-storable.
+     */
+    public function isNotStorable(): bool
+    {
+        return $this->data[FieldParam::NOT_STORABLE] ?? false;
+    }
+
+    /**
+     * Get a parameter value by a name.
+     */
+    public function getParam(string $name): mixed
+    {
+        return $this->data[$name] ?? null;
+    }
+
+    /**
+     * Has a parameter value.
+     */
+    public function hasParam(string $name): bool
+    {
+        return array_key_exists($name, $this->data);
+    }
+}

application/Espo/ORM/Defs/IndexDefs.php

@@ -0,0 +1,108 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Defs;
+
+use Espo\ORM\Defs\Params\IndexParam;
+
+/**
+ * Index definitions.
+ */
+class IndexDefs
+{
+    /** @var array<string, mixed> */
+    private $data;
+    private string $name;
+
+    private function __construct()
+    {}
+
+    /**
+     * @param array<string, mixed> $raw
+     */
+    public static function fromRaw(array $raw, string $name): self
+    {
+        $obj = new self();
+        $obj->data = $raw;
+        $obj->name = $name;
+
+        return $obj;
+    }
+
+    /**
+     * Get a name.
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * Get a key.
+     */
+    public function getKey(): string
+    {
+        return $this->data[IndexParam::KEY] ?? '';
+    }
+
+    /**
+     * Whether is unique.
+     */
+    public function isUnique(): bool
+    {
+        // For bc.
+        if (($this->data['unique'] ?? false)) {
+            return true;
+        }
+
+        $type = $this->data[IndexParam::TYPE] ?? null;
+
+        return $type === 'unique';
+    }
+
+    /**
+     * Get a column list.
+     *
+     * @return string[]
+     */
+    public function getColumnList(): array
+    {
+        return $this->data[IndexParam::COLUMNS] ?? [];
+    }
+
+    /**
+     * Get a flag list.
+     *
+     * @return string[]
+     */
+    public function getFlagList(): array
+    {
+        return $this->data[IndexParam::FLAGS] ?? [];
+    }
+}

application/Espo/ORM/Defs/Params/AttributeParam.php

@@ -0,0 +1,96 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Defs\Params;
+
+/**
+ * An attribute parameter.
+ */
+class AttributeParam
+{
+    /**
+     * A type.
+     */
+    public const TYPE = 'type';
+
+    /**
+     * Not stored in database.
+     */
+    public const NOT_STORABLE = 'notStorable';
+
+    /**
+     * A database type.
+     */
+    public const DB_TYPE = 'dbType';
+
+    /**
+     * A length.
+     */
+    public const LEN = 'len';
+
+    /**
+     * Not null.
+     */
+    public const NOT_NULL = 'notNull';
+
+    /**
+     * Autoincrement.
+     */
+    public const AUTOINCREMENT = 'autoincrement';
+
+    /**
+     * A default value.
+     */
+    public const DEFAULT = 'default';
+
+    /**
+     * A relation. For foreign attributes.
+     */
+    public const RELATION = 'relation';
+
+    /**
+     * A foreign attribute name. For foreign attributes.
+     */
+    public const FOREIGN = 'foreign';
+
+    /**
+     * Precision.
+     */
+    public const PRECISION = 'precision';
+
+    /**
+     * Scale.
+     */
+    public const SCALE = 'scale';
+
+    /**
+     * Dependee attributes.
+     */
+    public const DEPENDEE_ATTRIBUTE_LIST = 'dependeeAttributeList';
+}

application/Espo/ORM/Defs/Params/EntityParam.php

@@ -0,0 +1,56 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Defs\Params;
+
+/**
+ * An entity parameter.
+ */
+class EntityParam
+{
+    /**
+     * Fields.
+     */
+    public const FIELDS = 'fields';
+
+    /**
+     * Attributes.
+     */
+    public const ATTRIBUTES = 'attributes';
+
+    /**
+     * Relations.
+     */
+    public const RELATIONS = 'relations';
+
+    /**
+     * Indexes.
+     */
+    public const INDEXES = 'indexes';
+}

application/Espo/ORM/Defs/Params/FieldParam.php

@@ -0,0 +1,106 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Defs\Params;
+
+/**
+ * A field parameter.
+ */
+class FieldParam
+{
+    /**
+     * A type.
+     */
+    public const TYPE = 'type';
+
+    /**
+     * Not stored in database.
+     */
+    public const NOT_STORABLE = 'notStorable';
+
+    /**
+     * A database type.
+     */
+    public const DB_TYPE = 'dbType';
+
+    /**
+     * Autoincrement.
+     */
+    public const AUTOINCREMENT = 'autoincrement';
+
+    /**
+     * A max length.
+     */
+    public const MAX_LENGTH = 'maxLength';
+
+    /**
+     * Not null.
+     */
+    public const NOT_NULL = 'notNull';
+
+    /**
+     * A default value.
+     */
+    public const DEFAULT = 'default';
+
+    /**
+     * Read-only.
+     */
+    public const READ_ONLY = 'readOnly';
+
+    /**
+     * Decimal.
+     */
+    public const DECIMAL = 'decimal';
+
+    /**
+     * Precision.
+     */
+    public const PRECISION = 'precision';
+
+    /**
+     * Scale.
+     */
+    public const SCALE = 'scale';
+
+    /**
+     * Dependee attributes.
+     */
+    public const DEPENDEE_ATTRIBUTE_LIST = 'dependeeAttributeList';
+
+    /**
+     * Foreign link.
+     */
+    public const LINK = 'link';
+
+    /**
+     * Foreign field.
+     */
+    public const FIELD = 'field';
+}

application/Espo/ORM/Defs/Params/IndexParam.php

@@ -0,0 +1,56 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Defs\Params;
+
+/**
+ * An index parameter.
+ */
+class IndexParam
+{
+    /**
+     * A type.
+     */
+    public const TYPE = 'type';
+
+    /**
+     * A key.
+     */
+    public const KEY = 'key';
+
+    /**
+     * Columns.
+     */
+    public const COLUMNS = 'columns';
+
+    /**
+     * Flags.
+     */
+    public const FLAGS = 'flags';
+}

application/Espo/ORM/Defs/Params/RelationParam.php

@@ -0,0 +1,110 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Defs\Params;
+
+/**
+ * A relation parameter.
+ */
+class RelationParam
+{
+    /**
+     * A type.
+     */
+    public const TYPE = 'type';
+
+    /**
+     * Indexes.
+     */
+    public const INDEXES = 'indexes';
+
+    /**
+     * A relation name.
+     */
+    public const RELATION_NAME = 'relationName';
+
+    /**
+     * A foreign entity type.
+     */
+    public const ENTITY = 'entity';
+
+    /**
+     * A foreign relation name.
+     */
+    public const FOREIGN = 'foreign';
+
+    /**
+     * Conditions.
+     */
+    public const CONDITIONS = 'conditions';
+
+    /**
+     * Additional columns.
+     */
+    public const ADDITIONAL_COLUMNS = 'additionalColumns';
+
+    /**
+     * A key.
+     */
+    public const KEY = 'key';
+
+    /**
+     * A foreign key.
+     */
+    public const FOREIGN_KEY = 'foreignKey';
+
+    /**
+     * Middle keys.
+     */
+    public const MID_KEYS = 'midKeys';
+
+    /**
+     * No join.
+     */
+    public const NO_JOIN = 'noJoin';
+
+    /**
+     * Deferred load.
+     */
+    public const DEFERRED_LOAD = 'deferredLoad';
+
+    /**
+     * Default order by. Applied on the entity level.
+     *
+     * @since 9.2.5
+     */
+    public const ORDER_BY = 'orderBy';
+
+    /**
+     * Default order. Applied on the entity level.
+     *
+     * @since 9.2.5
+     */
+    public const ORDER = 'order';
+}

application/Espo/ORM/Defs/RelationDefs.php

@@ -0,0 +1,362 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Defs;
+
+use Espo\ORM\Defs\Params\RelationParam;
+use Espo\ORM\Entity;
+
+use RuntimeException;
+
+/**
+ * Relation definitions.
+ */
+class RelationDefs
+{
+    /** @var array<string, mixed> */
+    private array $data;
+    private string $name;
+
+    private function __construct()
+    {}
+
+    /**
+     * @param array<string, mixed> $raw
+     */
+    public static function fromRaw(array $raw, string $name): self
+    {
+        $obj = new self();
+        $obj->data = $raw;
+        $obj->name = $name;
+
+        return $obj;
+    }
+
+    /**
+     * Get a name.
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * Get a type.
+     */
+    public function getType(): string
+    {
+        $type = $this->data[RelationParam::TYPE] ?? null;
+
+        if ($type === null) {
+            throw new RuntimeException("Relation '{$this->name}' has no type.");
+        }
+
+        return $type;
+    }
+
+    /**
+     * Whether is Many-to-Many.
+     */
+    public function isManyToMany(): bool
+    {
+        return $this->getType() === Entity::MANY_MANY;
+    }
+
+    /**
+     * Whether is Has-Many (One-to-Many).
+     */
+    public function isHasMany(): bool
+    {
+        return $this->getType() === Entity::HAS_MANY;
+    }
+
+    /**
+     * Whether is Has-One (Many-to-One or One-to-One).
+     */
+    public function isHasOne(): bool
+    {
+        return $this->getType() === Entity::HAS_ONE;
+    }
+
+    /**
+     * Whether is Has-Children (Parent-to-Children).
+     */
+    public function isHasChildren(): bool
+    {
+        return $this->getType() === Entity::HAS_CHILDREN;
+    }
+
+    /**
+     * Whether is Belongs-to (Many-to-One).
+     */
+    public function isBelongsTo(): bool
+    {
+        return $this->getType() === Entity::BELONGS_TO;
+    }
+
+    /**
+     * Whether is Belongs-to-Parent (Children-to-Parent).
+     */
+    public function isBelongsToParent(): bool
+    {
+        return $this->getType() === Entity::BELONGS_TO_PARENT;
+    }
+
+    /**
+     * Whether it has a foreign entity type is defined.
+     */
+    public function hasForeignEntityType(): bool
+    {
+        return isset($this->data[RelationParam::ENTITY]);
+    }
+
+    /**
+     * Get a foreign entity type.
+     *
+     * @throws RuntimeException
+     */
+    public function getForeignEntityType(): string
+    {
+        if (!$this->hasForeignEntityType()) {
+            throw new RuntimeException("No 'entity' parameter defined in the relation '{$this->name}'.");
+        }
+
+        return $this->data[RelationParam::ENTITY];
+    }
+
+    /**
+     * Get a foreign entity type.
+     */
+    public function tryGetForeignEntityType(): ?string
+    {
+        if (!$this->hasForeignEntityType()) {
+            return null;
+        }
+
+        return $this->getForeignEntityType();
+    }
+
+    /**
+     * Whether it has a foreign relation name.
+     */
+    public function hasForeignRelationName(): bool
+    {
+        return isset($this->data[RelationParam::FOREIGN]);
+    }
+
+    /**
+     * Try to get a foreign relation name.
+     *
+     * @since 8.3.0
+     */
+    public function tryGetForeignRelationName(): ?string
+    {
+        if (!$this->hasForeignRelationName()) {
+            return null;
+        }
+
+        return $this->getForeignRelationName();
+    }
+
+    /**
+     * Get a foreign relation name.
+     *
+     * @throws RuntimeException
+     */
+    public function getForeignRelationName(): string
+    {
+        if (!$this->hasForeignRelationName()) {
+            throw new RuntimeException("No 'foreign' parameter defined in the relation '{$this->name}'.");
+        }
+
+        return $this->data[RelationParam::FOREIGN];
+    }
+
+    /**
+     * Whether a foreign key is defined.
+     */
+    public function hasForeignKey(): bool
+    {
+        return isset($this->data[RelationParam::FOREIGN_KEY]);
+    }
+
+    /**
+     * Get a foreign key.
+     *
+     * @throws RuntimeException
+     */
+    public function getForeignKey(): string
+    {
+        if (!$this->hasForeignKey()) {
+            throw new RuntimeException("No 'foreignKey' parameter defined in the relation '{$this->name}'.");
+        }
+
+        return $this->data[RelationParam::FOREIGN_KEY];
+    }
+
+    /**
+     * Whether a key is defined.
+     */
+    public function hasKey(): bool
+    {
+        return isset($this->data[RelationParam::KEY]);
+    }
+
+    /**
+     * Get a key.
+     * @throws RuntimeException
+     */
+    public function getKey(): string
+    {
+        if (!$this->hasKey()) {
+            throw new RuntimeException("No 'key' parameter defined in the relation '{$this->name}'.");
+        }
+
+        return $this->data[RelationParam::KEY];
+    }
+
+    /**
+     * Whether a mid-key is defined. For Many-to-Many relationships only.
+     */
+    public function hasMidKey(): bool
+    {
+        return !is_null($this->data[RelationParam::MID_KEYS][0] ?? null);
+    }
+
+    /**
+     * Get a mid-key. For Many-to-Many relationships only.
+     *
+     * @throws RuntimeException
+     */
+    public function getMidKey(): string
+    {
+        if (!$this->hasMidKey()) {
+            throw new RuntimeException("No 'midKey' parameter defined in the relation '{$this->name}'.");
+        }
+
+        return $this->data[RelationParam::MID_KEYS][0];
+    }
+
+    /**
+     * Whether a foreign mid-key is defined. For Many-to-Many relationships only.
+     *
+     * @throws RuntimeException
+     */
+    public function hasForeignMidKey(): bool
+    {
+        return !is_null($this->data[RelationParam::MID_KEYS][1] ?? null);
+    }
+
+    /**
+     * Get a foreign mid-key. For Many-to-Many relationships only.
+     *
+     * @throws RuntimeException
+     */
+    public function getForeignMidKey(): string
+    {
+        if (!$this->hasForeignMidKey()) {
+            throw new RuntimeException("No 'foreignMidKey' parameter defined in the relation '{$this->name}'.");
+        }
+
+        return $this->data[RelationParam::MID_KEYS][1];
+    }
+
+    /**
+     * Whether a relationship name is defined.
+     */
+    public function hasRelationshipName(): bool
+    {
+        return isset($this->data[RelationParam::RELATION_NAME]);
+    }
+
+    /**
+     * Get a relationship name.
+     *
+     * @throws RuntimeException
+     */
+    public function getRelationshipName(): string
+    {
+        if (!$this->hasRelationshipName()) {
+            throw new RuntimeException("No 'relationName' parameter defined in the relation '{$this->name}'.");
+        }
+
+        return $this->data[RelationParam::RELATION_NAME];
+    }
+
+    /**
+     * Get indexes.
+     *
+     * @return IndexDefs[]
+     * @throws RuntimeException
+     */
+    public function getIndexList(): array
+    {
+        if ($this->getType() !== Entity::MANY_MANY) {
+            throw new RuntimeException("Can't get indexes.");
+        }
+
+        $list = [];
+
+        foreach (($this->data[RelationParam::INDEXES] ?? []) as $name => $item) {
+            $list[] = IndexDefs::fromRaw($item, $name);
+        }
+
+        return $list;
+    }
+
+    /**
+     * Get additional middle table conditions.
+     *
+     * @return array<string, ?scalar>
+     */
+    public function getConditions(): array
+    {
+        if ($this->getType() !== Entity::MANY_MANY) {
+            throw new RuntimeException("Can't get conditions for non many-many relationship.");
+        }
+
+        return $this->getParam(RelationParam::CONDITIONS) ?? [];
+    }
+
+    /**
+     * Whether a parameter is set.
+     */
+    public function hasParam(string $name): bool
+    {
+        return array_key_exists($name, $this->data);
+    }
+
+    /**
+     * Get a parameter value by a name.
+     */
+    public function getParam(string $name): mixed
+    {
+        return $this->data[$name] ?? null;
+    }
+}

application/Espo/ORM/Entity.php

@@ -0,0 +1,213 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM;
+
+use Espo\ORM\Type\AttributeType;
+use Espo\ORM\Type\RelationType;
+use RuntimeException;
+use stdClass;
+
+/**
+ * An entity. Represents a single record in DB.
+ */
+interface Entity
+{
+    public const ID = AttributeType::ID;
+    public const VARCHAR = AttributeType::VARCHAR;
+    public const INT = AttributeType::INT;
+    public const FLOAT = AttributeType::FLOAT;
+    public const TEXT = AttributeType::TEXT;
+    public const BOOL = AttributeType::BOOL;
+    public const FOREIGN_ID = AttributeType::FOREIGN_ID;
+    public const FOREIGN = AttributeType::FOREIGN;
+    public const FOREIGN_TYPE = AttributeType::FOREIGN_TYPE;
+    public const DATE = AttributeType::DATE;
+    public const DATETIME = AttributeType::DATETIME;
+    public const JSON_ARRAY = AttributeType::JSON_ARRAY;
+    public const JSON_OBJECT = AttributeType::JSON_OBJECT;
+    public const PASSWORD = AttributeType::PASSWORD;
+
+    public const MANY_MANY = RelationType::MANY_MANY;
+    public const HAS_MANY = RelationType::HAS_MANY;
+    public const BELONGS_TO = RelationType::BELONGS_TO;
+    public const HAS_ONE = RelationType::HAS_ONE;
+    public const BELONGS_TO_PARENT = RelationType::BELONGS_TO_PARENT;
+    public const HAS_CHILDREN = RelationType::HAS_CHILDREN;
+
+    /**
+     * Get an entity ID.
+     *
+     * @return non-empty-string
+     * @throws RuntimeException If an ID is not set.
+     */
+    public function getId(): string;
+
+    /**
+     * Whether an ID is set.
+     */
+    public function hasId(): bool;
+
+    /**
+     * Reset all attributes (empty an entity).
+     */
+    public function reset(): void;
+
+    /**
+     * Set an attribute or multiple attributes.
+     *
+     * Two usage options:
+     * - `set($attribute, $value)`
+     * - `set($valueMap)`
+     *
+     * @param string|stdClass|array<string, mixed> $attribute
+     * @param mixed $value
+     */
+    public function set($attribute, $value = null): static;
+
+    /**
+     * Set multiple attributes.
+     *
+     * @param array<string, mixed>|stdClass $valueMap Values.
+     * @since v8.1.0.
+     */
+    public function setMultiple(array|stdClass $valueMap): static;
+
+    /**
+     * Get an attribute value.
+     *
+     * @return mixed
+     */
+    public function get(string $attribute);
+
+    /**
+     * Whether an attribute value is set.
+     */
+    public function has(string $attribute): bool;
+
+    /**
+     * Clear an attribute value.
+     */
+    public function clear(string $attribute): void;
+
+    /**
+     * Get an entity type.
+     */
+    public function getEntityType(): string;
+
+    /**
+     * Get attribute list defined for an entity type.
+     *
+     * @return string[]
+     */
+    public function getAttributeList(): array;
+
+    /**
+     * Get relation list defined for an entity type.
+     *
+     * @return string[]
+     */
+    public function getRelationList(): array;
+
+    /**
+     * Whether an entity type has an attribute defined.
+     */
+    public function hasAttribute(string $attribute): bool;
+
+    /**
+     * Whether an entity type has a relation defined.
+     */
+    public function hasRelation(string $relation): bool;
+
+    /**
+     * Get an attribute type.
+     */
+    public function getAttributeType(string $attribute): ?string;
+
+    /**
+     * Get a relation type.
+     */
+    public function getRelationType(string $relation): ?string;
+
+    /**
+     * Whether an entity is new.
+     */
+    public function isNew(): bool;
+
+    /**
+     * Set an entity as fetched. All current attribute values will be set as those that are fetched
+     * from the database.
+     */
+    public function setAsFetched(): void;
+
+    /**
+     * Whether is fetched from the database.
+     */
+    public function isFetched(): bool;
+
+    /**
+     * Whether an attribute was changed (since syncing with the database).
+     */
+    public function isAttributeChanged(string $name): bool;
+
+    /**
+     * Get a fetched value of a specific attribute.
+     *
+     * @return mixed
+     */
+    public function getFetched(string $attribute);
+
+    /**
+     * Whether a fetched value is set for a specific attribute.
+     */
+    public function hasFetched(string $attribute): bool;
+
+    /**
+     * Set a fetched value for a specific attribute.
+     *
+     * @param mixed $value
+     */
+    public function setFetched(string $attribute, $value): static;
+
+    /**
+     * Get values.
+     */
+    public function getValueMap(): stdClass;
+
+    /**
+     * Set as not new. Meaning the entity is fetched or already saved.
+     */
+    public function setAsNotNew(): void;
+
+    /**
+     * Copy all current values to fetched values. All current attribute values will be set as those
+     * that are fetched from DB.
+     */
+    public function updateFetchedValues(): void;
+}

application/Espo/ORM/EntityCollection.php

@@ -0,0 +1,471 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM;
+
+use Espo\ORM\Name\Attribute;
+use Iterator;
+use Countable;
+use ArrayAccess;
+use SeekableIterator;
+use RuntimeException;
+use OutOfBoundsException;
+use InvalidArgumentException;
+use Closure;
+
+/**
+ * A standard collection of entities. It allocates a memory for all entities.
+ *
+ * @template TEntity of Entity = Entity
+ * @implements Iterator<int, TEntity>
+ * @implements Collection<TEntity>
+ * @implements ArrayAccess<int, TEntity>
+ * @implements SeekableIterator<int, TEntity>
+ */
+class EntityCollection implements Collection, Iterator, Countable, ArrayAccess, SeekableIterator
+{
+    private ?EntityFactory $entityFactory;
+    private ?string $entityType;
+    private int $position = 0;
+    private bool $isFetched = false;
+    /** @var array<TEntity|array<string, mixed>> */
+    protected array $dataList = [];
+
+    /**
+     * @param array<TEntity|array<string, mixed>> $dataList
+     */
+    public function __construct(
+        array $dataList = [],
+        ?string $entityType = null,
+        ?EntityFactory $entityFactory = null
+    ) {
+        $this->dataList = $dataList;
+        $this->entityType = $entityType;
+        $this->entityFactory = $entityFactory;
+    }
+
+    public function rewind(): void
+    {
+        $this->position = 0;
+
+        while (!$this->valid() && $this->position <= $this->getLastValidKey()) {
+            $this->position ++;
+        }
+    }
+
+    /**
+     * @return TEntity
+     */
+    #[\ReturnTypeWillChange]
+    public function current()
+    {
+        return $this->getEntityByOffset($this->position);
+    }
+
+    /**
+     * @return int
+     */
+    #[\ReturnTypeWillChange]
+    public function key()
+    {
+        return $this->position;
+    }
+
+    public function next(): void
+    {
+        do {
+            $this->position ++;
+
+            $next = false;
+
+            if (!$this->valid() && $this->position <= $this->getLastValidKey()) {
+                $next = true;
+            }
+        } while ($next);
+    }
+
+    /**
+     * @return int
+     */
+    private function getLastValidKey()
+    {
+        $keys = array_keys($this->dataList);
+
+        $i = end($keys);
+
+        while ($i > 0) {
+            if (isset($this->dataList[$i])) {
+                break;
+            }
+
+            $i--;
+        }
+
+        return $i;
+    }
+
+    public function valid(): bool
+    {
+        return isset($this->dataList[$this->position]);
+    }
+
+    /**
+     * @param mixed $offset
+     */
+    public function offsetExists($offset): bool
+    {
+        return isset($this->dataList[$offset]);
+    }
+
+    /**
+     * @param mixed $offset
+     * @return ?TEntity
+     */
+    #[\ReturnTypeWillChange]
+    public function offsetGet($offset)
+    {
+        if (!isset($this->dataList[$offset])) {
+            return null;
+        }
+
+        return $this->getEntityByOffset($offset);
+    }
+
+    /**
+     * @param mixed $offset
+     * @param mixed $value
+     */
+    public function offsetSet($offset, $value): void
+    {
+        if (!($value instanceof Entity)) {
+            throw new InvalidArgumentException('Only Entity is allowed to be added to EntityCollection.');
+        }
+
+        /** @var TEntity $value */
+
+        if (is_null($offset)) {
+            $this->dataList[] = $value;
+
+            return;
+        }
+
+        $this->dataList[$offset] = $value;
+    }
+
+    /**
+     * @param mixed $offset
+     */
+    public function offsetUnset($offset): void
+    {
+        unset($this->dataList[$offset]);
+    }
+
+    public function count(): int
+    {
+        return count($this->dataList);
+    }
+
+    /**
+     * @param int $offset
+     */
+    public function seek($offset): void
+    {
+        $this->position = $offset;
+
+        if (!$this->valid()) {
+            throw new OutOfBoundsException("Invalid seek offset ($offset).");
+        }
+    }
+
+    /**
+     * @param TEntity $entity
+     */
+    public function append(Entity $entity): void
+    {
+        $this->dataList[] = $entity;
+    }
+
+    /**
+     * @param int $offset
+     * @return TEntity
+     */
+    private function getEntityByOffset($offset): Entity
+    {
+        if (!array_key_exists($offset, $this->dataList)) {
+            throw new RuntimeException();
+        }
+
+        $value = $this->dataList[$offset];
+
+        if ($value instanceof Entity) {
+            /** @var TEntity */
+            return $value;
+        }
+
+        if (is_array($value)) {
+            $this->dataList[$offset] = $this->buildEntityFromArray($value);
+
+            return $this->dataList[$offset];
+        }
+
+        throw new RuntimeException();
+    }
+
+    /**
+     * @param array<string, mixed> $dataArray
+     * @return TEntity
+     */
+    protected function buildEntityFromArray(array $dataArray): Entity
+    {
+        if (!$this->entityFactory) {
+            throw new RuntimeException("Can't build from array. EntityFactory was not passed to the constructor.");
+        }
+
+        assert($this->entityType !== null);
+
+        /** @var TEntity $entity */
+        $entity = $this->entityFactory->create($this->entityType);
+
+        $entity->set($dataArray);
+
+        if ($this->isFetched) {
+            $entity->setAsFetched();
+        }
+
+        return $entity;
+    }
+
+    /**
+     * Get an entity type.
+     */
+    public function getEntityType(): ?string
+    {
+        return $this->entityType;
+    }
+
+    /**
+     * @return array<TEntity|array<string, mixed>>
+     */
+    public function getDataList(): array
+    {
+        return $this->dataList;
+    }
+
+    /**
+     * Merge with another collection.
+     *
+     * @param EntityCollection<TEntity> $collection
+     */
+    public function merge(EntityCollection $collection): void
+    {
+        $incomingDataList = $collection->getDataList();
+
+        foreach ($incomingDataList as $v) {
+            if (!$this->contains($v)) {
+                $this->dataList[] = $v;
+            }
+        }
+    }
+
+    /**
+     * Whether a collection contains a specific item.
+     *
+     * @param TEntity|array<string, mixed> $value
+     */
+    public function contains($value): bool
+    {
+        if ($this->indexOf($value) !== false) {
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * @param TEntity|array<string, mixed> $value
+     * @return false|int
+     */
+    public function indexOf($value)
+    {
+        $index = 0;
+
+        if (is_array($value)) {
+            foreach ($this->dataList as $v) {
+                if (is_array($v)) {
+                    if ($value[Attribute::ID] == $v[Attribute::ID]) {
+                        return $index;
+                    }
+                } else if ($v instanceof Entity) {
+                    if ($value[Attribute::ID] == $v->getId()) {
+                        return $index;
+                    }
+                }
+
+                $index ++;
+            }
+        } else if ($value instanceof Entity) {
+            foreach ($this->dataList as $v) {
+                if (is_array($v)) {
+                    if ($value->getId() == $v[Attribute::ID]) {
+                        return $index;
+                    }
+                } else if ($v instanceof Entity) {
+                    if ($value === $v) {
+                        return $index;
+                    }
+                }
+
+                $index ++;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function getValueMapList(): array
+    {
+        $list = [];
+
+        foreach ($this as $entity) {
+            $item = $entity->getValueMap();
+
+            $list[] = $item;
+        }
+
+        return $list;
+    }
+
+    /**
+     * Mark as fetched from DB.
+     */
+    public function setAsFetched(): void
+    {
+        $this->isFetched = true;
+    }
+
+    /**
+     * Is fetched from DB.
+     */
+    public function isFetched(): bool
+    {
+        return $this->isFetched;
+    }
+
+    /**
+     * Create from SthCollection.
+     *
+     * @param SthCollection<TEntity> $sthCollection
+     * @return self<TEntity>
+     */
+    public static function fromSthCollection(SthCollection $sthCollection): self
+    {
+        $entityList = [];
+
+        foreach ($sthCollection as $entity) {
+            $entityList[] = $entity;
+        }
+
+        /** @var self<TEntity> $obj */
+        $obj = new EntityCollection($entityList, $sthCollection->getEntityType());
+        $obj->setAsFetched();
+
+        return $obj;
+    }
+
+    /**
+     * Filter.
+     *
+     * @param Closure(TEntity): bool $callback A filter callback.
+     * @return self<TEntity> A filtered collection. A new instance.
+     * @since 9.1.0
+     */
+    public function filter(Closure $callback): self
+    {
+        $newList = [];
+
+        foreach ($this as $entity) {
+            if ($callback($entity)) {
+                $newList[] = $entity;
+            }
+        }
+
+        return new EntityCollection($newList, $this->entityType, $this->entityFactory);
+    }
+
+    /**
+     * Sort.
+     *
+     * @param Closure(TEntity, TEntity): int $callback The comparison function.
+     * @return self<TEntity> A sorted collection. A new instance.
+     * @since 9.1.0
+     */
+    public function sort(Closure $callback): self
+    {
+        $newList = [...$this];
+
+        usort($newList, $callback);
+
+        return new EntityCollection($newList, $this->entityType, $this->entityFactory);
+    }
+
+    /**
+     * Reverse.
+     *
+     * @return self<TEntity> A reversed collection.
+     * @since 9.1.0
+     */
+    public function reverse(): self
+    {
+        $newList = array_reverse([...$this]);
+
+        return new EntityCollection($newList, $this->entityType, $this->entityFactory);
+    }
+
+    /**
+     * Find.
+     *
+     * @param Closure(TEntity): bool $callback A filter callback.
+     * @return ?TEntity
+     * @since 9.1.0
+     * @noinspection PhpDocSignatureInspection
+     */
+    public function find(Closure $callback): ?Entity
+    {
+        foreach ($this as $entity) {
+            if ($callback($entity)) {
+                return $entity;
+            }
+        }
+
+        return null;
+    }
+}

application/Espo/ORM/EntityFactory.php

@@ -0,0 +1,50 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM;
+
+use Espo\ORM\Value\ValueAccessorFactory;
+
+interface EntityFactory
+{
+    /**
+     * Create an entity.
+     */
+    public function create(string $entityType): Entity;
+
+    /**
+     * @internal
+     */
+    public function setEntityManager(EntityManager $entityManager): void;
+
+    /**
+     * @internal
+     */
+    public function setValueAccessorFactory(ValueAccessorFactory $valueAccessorFactory): void;
+}

application/Espo/ORM/EntityManager.php

@@ -0,0 +1,477 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM;
+
+use Espo\ORM\Defs\Defs;
+use Espo\ORM\Executor\DefaultQueryExecutor;
+use Espo\ORM\Executor\DefaultSqlExecutor;
+use Espo\ORM\Executor\QueryExecutor;
+use Espo\ORM\Executor\SqlExecutor;
+use Espo\ORM\QueryComposer\QueryComposer;
+use Espo\ORM\QueryComposer\QueryComposerFactory;
+use Espo\ORM\QueryComposer\QueryComposerWrapper;
+use Espo\ORM\Mapper\Mapper;
+use Espo\ORM\Mapper\MapperFactory;
+use Espo\ORM\Mapper\BaseMapper;
+use Espo\ORM\Relation\RelationsMap;
+use Espo\ORM\Repository\RDBRelation;
+use Espo\ORM\Repository\RepositoryFactory;
+use Espo\ORM\Repository\Repository;
+use Espo\ORM\Repository\RDBRepository;
+use Espo\ORM\Repository\Util as RepositoryUtil;
+use Espo\ORM\Locker\Locker;
+use Espo\ORM\Locker\BaseLocker;
+use Espo\ORM\Locker\MysqlLocker;
+use Espo\ORM\Value\ValueAccessorFactory;
+use Espo\ORM\Value\ValueFactoryFactory;
+use Espo\ORM\Value\AttributeExtractorFactory;
+use Espo\ORM\PDO\PDOProvider;
+
+use PDO;
+use RuntimeException;
+use stdClass;
+
+/**
+ * A central access point to ORM functionality.
+ */
+class EntityManager
+{
+    private CollectionFactory $collectionFactory;
+    private QueryComposer $queryComposer;
+    private QueryExecutor $queryExecutor;
+    private QueryBuilder $queryBuilder;
+    private SqlExecutor $sqlExecutor;
+    private TransactionManager $transactionManager;
+    private Locker $locker;
+
+    private const RDB_MAPPER_NAME = 'RDB';
+
+    /** @var array<string, Repository<Entity>> */
+    private $repositoryHash = [];
+    /** @var array<string, Mapper> */
+    private $mappers = [];
+
+    /**
+     * @param AttributeExtractorFactory<object> $attributeExtractorFactory
+     * @throws RuntimeException
+     */
+    public function __construct(
+        private DatabaseParams $databaseParams,
+        private Metadata $metadata,
+        private RepositoryFactory $repositoryFactory,
+        private EntityFactory $entityFactory,
+        private QueryComposerFactory $queryComposerFactory,
+        ValueFactoryFactory $valueFactoryFactory,
+        AttributeExtractorFactory $attributeExtractorFactory,
+        EventDispatcher $eventDispatcher,
+        private PDOProvider $pdoProvider,
+        private RelationsMap $relationsMap,
+        private ?MapperFactory $mapperFactory = null,
+        ?QueryExecutor $queryExecutor = null,
+        ?SqlExecutor $sqlExecutor = null,
+    ) {
+        if (!$this->databaseParams->getPlatform()) {
+            throw new RuntimeException("No 'platform' parameter.");
+        }
+
+        $valueAccessorFactory = new ValueAccessorFactory(
+            $valueFactoryFactory,
+            $attributeExtractorFactory,
+            $eventDispatcher
+        );
+
+        $this->entityFactory->setEntityManager($this);
+        $this->entityFactory->setValueAccessorFactory($valueAccessorFactory);
+
+        $this->initQueryComposer();
+
+        $this->sqlExecutor = $sqlExecutor ?? new DefaultSqlExecutor($this->pdoProvider);
+        $this->queryExecutor = $queryExecutor ??
+            new DefaultQueryExecutor($this->sqlExecutor, $this->getQueryComposer());
+        $this->queryBuilder = new QueryBuilder();
+        $this->collectionFactory = new CollectionFactory($this);
+        $this->transactionManager = new TransactionManager($this->pdoProvider->get(), $this->queryComposer);
+
+        $this->initLocker();
+    }
+
+    private function initQueryComposer(): void
+    {
+        $platform = $this->databaseParams->getPlatform() ?? '';
+
+        $this->queryComposer = $this->queryComposerFactory->create($platform);
+    }
+
+    private function initLocker(): void
+    {
+        $platform = $this->databaseParams->getPlatform() ?? '';
+
+        $className = BaseLocker::class;
+
+        if ($platform === 'Mysql') {
+            $className = MysqlLocker::class;
+        }
+
+        $this->locker = new $className($this->pdoProvider->get(), $this->queryComposer, $this->transactionManager);
+    }
+
+    /**
+     * Get the query composer.
+     */
+    public function getQueryComposer(): QueryComposerWrapper
+    {
+        return new QueryComposerWrapper($this->queryComposer);
+    }
+
+    /**
+     * Get the transaction manager.
+     */
+    public function getTransactionManager(): TransactionManager
+    {
+        return $this->transactionManager;
+    }
+
+    /**
+     * Get the locker.
+     */
+    public function getLocker(): Locker
+    {
+        return $this->locker;
+    }
+
+    /**
+     * Get a mapper.
+     */
+    public function getMapper(string $name = self::RDB_MAPPER_NAME): Mapper
+    {
+        if (!array_key_exists($name, $this->mappers)) {
+            $this->loadMapper($name);
+        }
+
+        return $this->mappers[$name];
+    }
+
+    private function loadMapper(string $name): void
+    {
+        if ($name === self::RDB_MAPPER_NAME) {
+            $mapper = new BaseMapper(
+                $this->pdoProvider->get(),
+                $this->entityFactory,
+                $this->collectionFactory,
+                $this->metadata,
+                $this->queryExecutor
+            );
+
+            $this->mappers[$name] = $mapper;
+
+            return;
+        }
+
+        if (!$this->mapperFactory) {
+            throw new RuntimeException("Could not create mapper '$name'. No mapper factory.");
+        }
+
+        $this->mappers[$name] = $this->mapperFactory->create($name);
+    }
+
+    /**
+     * Get an entity. If $id is null, a new entity instance is created.
+     * If an entity with a specified ID does not exist, then NULL is returned.
+     * @deprecated As of v9.0. Use getNewEntity and getEntityById instead.
+     * @todo Remove in v11.0.
+     */
+    public function getEntity(string $entityType, ?string $id = null): ?Entity
+    {
+        if (!$this->hasRepository($entityType)) {
+            throw new RuntimeException("ORM: Repository '$entityType' does not exist.");
+        }
+
+        if ($id === null) {
+            return $this->getRepository($entityType)->getNew();
+        }
+
+        return $this->getRepository($entityType)->getById($id);
+    }
+
+    /**
+     * Create a new entity instance (w/o storing to DB).
+     */
+    public function getNewEntity(string $entityType): Entity
+    {
+        /**
+         * @var Entity
+         * @noinspection PhpDeprecationInspection
+         */
+        return $this->getEntity($entityType);
+    }
+
+    /**
+     * Get an entity by ID. If an entity does not exist, NULL is returned.
+     */
+    public function getEntityById(string $entityType, string $id): ?Entity
+    {
+        /** @noinspection PhpDeprecationInspection */
+        return $this->getEntity($entityType, $id);
+    }
+
+    /**
+     * Store an entity.
+     *
+     * @param array<string, mixed> $options Options.
+     */
+    public function saveEntity(Entity $entity, array $options = []): void
+    {
+        $entityType = $entity->getEntityType();
+
+        $this->getRepository($entityType)->save($entity, $options);
+    }
+
+    /**
+     * Mark an entity as deleted (in database).
+     *
+     * @param array<string, mixed> $options Options.
+     */
+    public function removeEntity(Entity $entity, array $options = []): void
+    {
+        $entityType = $entity->getEntityType();
+
+        $this->getRepository($entityType)->remove($entity, $options);
+    }
+
+    /**
+     * Refresh an entity from the database, overwriting made changes, if any.
+     * Can be used to fetch attributes that were not fetched initially.
+     *
+     * @throws RuntimeException
+     */
+    public function refreshEntity(Entity $entity): void
+    {
+        if ($entity->isNew()) {
+            throw new RuntimeException("Can't refresh a new entity.");
+        }
+
+        if (!$entity->hasId()) {
+            throw new RuntimeException("Can't refresh an entity w/o ID.");
+        }
+
+        $fetchedEntity = $this->getEntityById($entity->getEntityType(), $entity->getId());
+
+        if (!$fetchedEntity) {
+            throw new RuntimeException("Can't refresh a non-existent entity.");
+        }
+
+        $this->relationsMap->get($entity)?->resetAll();
+
+        $prevMap = get_object_vars($entity->getValueMap());
+        $fetchedMap = get_object_vars($fetchedEntity->getValueMap());
+
+        foreach (array_keys($prevMap) as $attribute) {
+            if (!array_key_exists($attribute, $fetchedMap)) {
+                $entity->clear($attribute);
+            }
+        }
+
+        $entity->set($fetchedMap);
+        $entity->setAsFetched();
+    }
+
+    /**
+     * Create entity (and store to database).
+     *
+     * @param stdClass|array<string, mixed> $data Entity attributes.
+     * @param array<string, mixed> $options Options.
+     */
+    public function createEntity(string $entityType, $data = [], array $options = []): Entity
+    {
+        $entity = $this->getNewEntity($entityType);
+        $entity->set($data);
+        $this->saveEntity($entity, $options);
+
+        return $entity;
+    }
+
+    /**
+     * Check whether a repository for a specific entity type exist.
+     */
+    public function hasRepository(string $entityType): bool
+    {
+        return $this->getMetadata()->has($entityType);
+    }
+
+    /**
+     * Get a repository for a specific entity type.
+     *
+     * @return Repository<Entity>
+     */
+    public function getRepository(string $entityType): Repository
+    {
+        if (!$this->hasRepository($entityType)) {
+            throw new RuntimeException("Repository '$entityType' does not exist.");
+        }
+
+        if (!array_key_exists($entityType, $this->repositoryHash)) {
+            $this->repositoryHash[$entityType] = $this->repositoryFactory->create($entityType);
+        }
+
+        return $this->repositoryHash[$entityType];
+    }
+
+    /**
+     * Get an RDB repository for a specific entity type.
+     *
+     * @return RDBRepository<Entity>
+     */
+    public function getRDBRepository(string $entityType): RDBRepository
+    {
+        $repository = $this->getRepository($entityType);
+
+        if (!$repository instanceof RDBRepository) {
+            throw new RuntimeException("Repository '$entityType' is not RDB.");
+        }
+
+        return $repository;
+    }
+
+    /**
+     * Get an RDB repository by an entity class name.
+     *
+     * @template T of Entity
+     * @param class-string<T> $className An entity class name.
+     * @return RDBRepository<T>
+     */
+    public function getRDBRepositoryByClass(string $className): RDBRepository
+    {
+        $entityType = RepositoryUtil::getEntityTypeByClass($className);
+
+        /** @var RDBRepository<T> */
+        return $this->getRDBRepository($entityType);
+    }
+
+    /**
+     * Get a repository by an entity class name.
+     *
+     * @template T of Entity
+     * @param class-string<T> $className An entity class name.
+     * @return Repository<T>
+     */
+    public function getRepositoryByClass(string $className): Repository
+    {
+        $entityType = RepositoryUtil::getEntityTypeByClass($className);
+
+        /** @var Repository<T> */
+        return $this->getRepository($entityType);
+    }
+
+    /**
+     * Get an access point for a specific relation of a record.
+     *
+     * @return RDBRelation<Entity>
+     * @since 8.4.0
+     */
+    public function getRelation(Entity $entity, string $relationName): RDBRelation
+    {
+        return $this->getRDBRepository($entity->getEntityType())->getRelation($entity, $relationName);
+    }
+
+    /**
+     * Get metadata definitions.
+     */
+    public function getDefs(): Defs
+    {
+        return $this->metadata->getDefs();
+    }
+
+    /**
+     * Get a query builder.
+     */
+    public function getQueryBuilder(): QueryBuilder
+    {
+        return $this->queryBuilder;
+    }
+
+    /**
+     * Get metadata.
+     */
+    public function getMetadata(): Metadata
+    {
+        return $this->metadata;
+    }
+
+    /**
+     * Get the entity factory.
+     */
+    public function getEntityFactory(): EntityFactory
+    {
+        return $this->entityFactory;
+    }
+
+    /**
+     * Get the collection factory.
+     */
+    public function getCollectionFactory(): CollectionFactory
+    {
+        return $this->collectionFactory;
+    }
+
+    /**
+     * Get a Query Executor.
+     */
+    public function getQueryExecutor(): QueryExecutor
+    {
+        return $this->queryExecutor;
+    }
+
+    /**
+     * Get SQL Executor.
+     */
+    public function getSqlExecutor(): SqlExecutor
+    {
+        return $this->sqlExecutor;
+    }
+
+    /**
+     * @deprecated As of v7.0. Use `getCollectionFactory`.
+     * @param array<string, mixed> $data
+     * @return EntityCollection<Entity>
+     * @todo Remove in v10.0.
+     */
+    public function createCollection(?string $entityType = null, array $data = []): EntityCollection
+    {
+        return $this->collectionFactory->create($entityType, $data);
+    }
+
+    /**
+     * @deprecated As of v7.0. Use the Query Builder instead. Otherwise, code will be not portable.
+     */
+    public function getPDO(): PDO
+    {
+        return $this->pdoProvider->get();
+    }
+}

application/Espo/ORM/EventDispatcher.php

@@ -0,0 +1,79 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM;
+
+use Closure;
+
+/**
+ * Event dispatcher.
+ */
+class EventDispatcher
+{
+    /** @var array{'metadataUpdate': Closure[]} */
+    private array $data;
+
+    private const METADATA_UPDATE = 'metadataUpdate';
+
+    public function __construct()
+    {
+        $this->data = [
+            self::METADATA_UPDATE => [],
+        ];
+    }
+
+    public function subscribeToMetadataUpdate(Closure $callback): void
+    {
+        $this->data[self::METADATA_UPDATE][] = $callback;
+    }
+
+    /**
+     * @internal
+     * @since 8.4.0
+     */
+    public function unsubscribeFromMetadataUpdate(Closure $closure): void
+    {
+        $list = &$this->data[self::METADATA_UPDATE];
+
+        $index = array_search($closure, $list);
+
+        if ($index !== false) {
+            unset($list[$index]);
+
+            $list = array_values($list);
+        }
+    }
+
+    public function dispatchMetadataUpdate(): void
+    {
+        foreach ($this->data[self::METADATA_UPDATE] as $callback) {
+            $callback();
+        }
+    }
+}

application/Espo/ORM/Executor/DefaultQueryExecutor.php

@@ -0,0 +1,50 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Executor;
+
+use Espo\ORM\Query\Query;
+use Espo\ORM\QueryComposer\QueryComposerWrapper;
+
+use PDOStatement;
+
+class DefaultQueryExecutor implements QueryExecutor
+{
+    public function __construct(
+        private SqlExecutor $sqlExecutor,
+        private QueryComposerWrapper $queryComposer
+    ) {}
+
+    public function execute(Query $query): PDOStatement
+    {
+        $sql = $this->queryComposer->compose($query);
+
+        return $this->sqlExecutor->execute($sql, true);
+    }
+}

application/Espo/ORM/Executor/DefaultSqlExecutor.php

@@ -0,0 +1,108 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Executor;
+
+use Espo\ORM\PDO\PDOProvider;
+use Psr\Log\LoggerInterface;
+
+use PDO;
+use PDOStatement;
+use PDOException;
+use Exception;
+use RuntimeException;
+
+class DefaultSqlExecutor implements SqlExecutor
+{
+    private const MAX_ATTEMPT_COUNT = 4;
+
+    private PDO $pdo;
+
+    public function __construct(
+        PDOProvider $pdoProvider,
+        private ?LoggerInterface $logger = null,
+        private bool $logAll = false,
+        private bool $logFailed = false
+    ) {
+        $this->pdo = $pdoProvider->get();
+    }
+
+    /**
+     * Execute a query.
+     */
+    public function execute(string $sql, bool $rerunIfDeadlock = false): PDOStatement
+    {
+        if ($this->logAll) {
+            $this->logger?->info("SQL: " . $sql, ['isSql' => true]);
+        }
+
+        if (!$rerunIfDeadlock) {
+            return $this->executeSqlWithDeadlockHandling($sql, 1);
+        }
+
+        return $this->executeSqlWithDeadlockHandling($sql);
+    }
+
+    private function executeSqlWithDeadlockHandling(string $sql, ?int $counter = null): PDOStatement
+    {
+        $counter = $counter ?? self::MAX_ATTEMPT_COUNT;
+
+        try {
+            $sth = $this->pdo->query($sql);
+        } catch (Exception $e) {
+            $counter--;
+
+            if ($counter === 0 || !$this->isExceptionIsDeadlock($e)) {
+                if ($this->logFailed) {
+                    $this->logger?->error("SQL failed: " . $sql, ['isSql' => true]);
+                }
+
+                /** @var PDOException $e */
+                throw $e;
+            }
+
+            return $this->executeSqlWithDeadlockHandling($sql, $counter);
+        }
+
+        if (!$sth) {
+            throw new RuntimeException("Query execution failure.");
+        }
+
+        return $sth;
+    }
+
+    private function isExceptionIsDeadlock(Exception $e): bool
+    {
+        if (!$e instanceof PDOException) {
+            return false;
+        }
+
+        return isset($e->errorInfo) && $e->errorInfo[0] == 40001 && $e->errorInfo[1] == 1213;
+    }
+}

application/Espo/ORM/Executor/QueryExecutor.php

@@ -0,0 +1,45 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Executor;
+
+use Espo\ORM\Query\Query;
+
+use PDOStatement;
+
+/**
+ * Executes queries by given query params instances.
+ */
+interface QueryExecutor
+{
+    /**
+     * Execute a query.
+     */
+    public function execute(Query $query): PDOStatement;
+}

application/Espo/ORM/Executor/SqlExecutor.php

@@ -0,0 +1,43 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Executor;
+
+use PDOStatement;
+
+/**
+ * Executes SQL queries.
+ */
+interface SqlExecutor
+{
+    /**
+     * Execute a query.
+     */
+    public function execute(string $sql, bool $rerunIfDeadlock = false): PDOStatement;
+}

application/Espo/ORM/Locker/BaseLocker.php

@@ -0,0 +1,122 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Locker;
+
+use Espo\ORM\Query\LockTableBuilder;
+use Espo\ORM\QueryComposer\QueryComposer;
+use Espo\ORM\TransactionManager;
+
+use PDO;
+use RuntimeException;
+
+class BaseLocker implements Locker
+{
+    private bool $isLocked = false;
+
+    public function __construct(
+        private PDO $pdo,
+        private QueryComposer $queryComposer,
+        private TransactionManager $transactionManager
+    ) {}
+
+    /**
+     * {@inheritdoc}
+     */
+    public function isLocked(): bool
+    {
+        return $this->isLocked;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function lockExclusive(string $entityType): void
+    {
+        $this->isLocked = true;
+
+        $this->transactionManager->start();
+
+        $query = (new LockTableBuilder())
+            ->table($entityType)
+            ->inExclusiveMode()
+            ->build();
+
+        $sql = $this->queryComposer->composeLockTable($query);
+
+        $this->pdo->exec($sql);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function lockShare(string $entityType): void
+    {
+        $this->isLocked = true;
+
+        $this->transactionManager->start();
+
+        $query = (new LockTableBuilder())
+            ->table($entityType)
+            ->inShareMode()
+            ->build();
+
+        $sql = $this->queryComposer->composeLockTable($query);
+
+        $this->pdo->exec($sql);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function commit(): void
+    {
+        if (!$this->isLocked) {
+            throw new RuntimeException("Can't commit, it was not locked.");
+        }
+
+        $this->transactionManager->commit();
+
+        $this->isLocked = false;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function rollback(): void
+    {
+        if (!$this->isLocked) {
+            throw new RuntimeException("Can't rollback, it was not locked.");
+        }
+
+        $this->transactionManager->rollback();
+
+        $this->isLocked = false;
+    }
+}

application/Espo/ORM/Locker/Locker.php

@@ -0,0 +1,62 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Locker;
+
+/**
+ * Locks and unlocks tables.
+ * Wraps operations between lock and unlock into a transaction.
+ */
+interface Locker
+{
+    /**
+     * Whether any table has been locked.
+     */
+    public function isLocked(): bool;
+
+    /**
+     * Locks a table in an exclusive mode. Starts a transaction on first call.
+     */
+    public function lockExclusive(string $entityType): void;
+
+    /**
+     * Locks a table in a share mode. Starts a transaction on first call.
+     */
+    public function lockShare(string $entityType): void;
+
+    /**
+     * Commits changes and unlocks tables.
+     */
+    public function commit(): void;
+
+    /**
+     * Rollbacks changes and unlocks tables.
+     */
+    public function rollback(): void;
+}

application/Espo/ORM/Locker/MysqlLocker.php

@@ -0,0 +1,138 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Locker;
+
+use Espo\ORM\QueryComposer\QueryComposer;
+use Espo\ORM\QueryComposer\MysqlQueryComposer;
+use Espo\ORM\Query\LockTableBuilder;
+use Espo\ORM\TransactionManager;
+
+use PDO;
+use RuntimeException;
+
+/**
+ * Transactions within locking is not supported for MySQL.
+ */
+class MysqlLocker implements Locker
+{
+    private MysqlQueryComposer $queryComposer;
+    /** @phpstan-ignore-next-line */
+    private TransactionManager $transactionManager;
+
+    private bool $isLocked = false;
+
+    public function __construct(
+        private PDO $pdo,
+        QueryComposer $queryComposer,
+        TransactionManager $transactionManager
+    ) {
+        $this->transactionManager = $transactionManager;
+
+        if (!$queryComposer instanceof MysqlQueryComposer) {
+            throw new RuntimeException();
+        }
+
+        $this->queryComposer = $queryComposer;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function isLocked(): bool
+    {
+        return $this->isLocked;
+    }
+    /**
+     * {@inheritdoc}
+     */
+    public function lockExclusive(string $entityType): void
+    {
+        $this->isLocked = true;
+
+        $query = (new LockTableBuilder())
+            ->table($entityType)
+            ->inExclusiveMode()
+            ->build();
+
+        $sql = $this->queryComposer->composeLockTable($query);
+
+        $this->pdo->exec($sql);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function lockShare(string $entityType): void
+    {
+        $this->isLocked = true;
+
+        $query = (new LockTableBuilder())
+            ->table($entityType)
+            ->inShareMode()
+            ->build();
+
+        $sql = $this->queryComposer->composeLockTable($query);
+
+        $this->pdo->exec($sql);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function commit(): void
+    {
+        if (!$this->isLocked) {
+            throw new RuntimeException("Can't commit, it was not locked.");
+        }
+
+        $this->isLocked = false;
+
+        $sql = $this->queryComposer->composeUnlockTables();
+
+        $this->pdo->exec($sql);
+    }
+
+    /**
+     * Lift locking.
+     * Rolling back within locking is not supported for MySQL.
+     */
+    public function rollback(): void
+    {
+        if (!$this->isLocked) {
+            throw new RuntimeException("Can't rollback, it was not locked.");
+        }
+
+        $this->isLocked = false;
+
+        $sql = $this->queryComposer->composeUnlockTables();
+
+        $this->pdo->exec($sql);
+    }
+}

application/Espo/ORM/Mapper/Helper.php

@@ -0,0 +1,156 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Mapper;
+
+use Espo\ORM\Entity;
+use Espo\ORM\Metadata;
+
+use Espo\ORM\Name\Attribute;
+use RuntimeException;
+
+class Helper
+{
+    public function __construct(private Metadata $metadata)
+    {}
+
+    /**
+     * @return array{
+     *   key: string,
+     *   foreignKey: string,
+     *   foreignType?: string,
+     *   nearKey?: string,
+     *   distantKey?: string,
+     *   typeKey?: string,
+     * }
+     */
+    public function getRelationKeys(Entity $entity, string $relationName): array
+    {
+        $entityType = $entity->getEntityType();
+
+        $defs = $this->metadata->getDefs()
+            ->getEntity($entityType)
+            ->getRelation($relationName);
+
+        $type = $defs->getType();
+
+        switch ($type) {
+
+            case Entity::BELONGS_TO:
+                $key = $defs->hasKey() ?
+                    $defs->getKey() :
+                    $relationName . 'Id';
+
+                $foreignKey = $defs->hasForeignKey() ?
+                    $defs->getForeignKey() :
+                    Attribute::ID;
+
+                return [
+                    'key' => $key,
+                    'foreignKey' => $foreignKey,
+                ];
+
+            case Entity::HAS_MANY:
+            case Entity::HAS_ONE:
+                $key = $defs->hasKey() ? $defs->getKey() : Attribute::ID;
+
+                $foreign = $defs->hasForeignRelationName() ?
+                    $defs->getForeignRelationName() :
+                    null;
+
+                $foreignKey = $defs->hasForeignKey() ?
+                    $defs->getForeignKey() :
+                    null;
+
+                if (!$foreignKey && $foreign) {
+                    $foreignKey = $foreign . 'Id';
+                }
+
+                if (!$foreignKey) {
+                    $foreignKey = lcfirst($entity->getEntityType()) . 'Id';
+                }
+
+                return [
+                    'key' => $key,
+                    'foreignKey' => $foreignKey,
+                ];
+
+            case Entity::HAS_CHILDREN:
+                $key = $defs->hasKey() ? $defs->getKey() : Attribute::ID;
+
+                $foreignKey = $defs->hasForeignKey() ?
+                    $defs->getForeignKey() :
+                    'parentId';
+
+                $foreignType = $defs->getParam('foreignType') ?? 'parentType';
+
+                return [
+                    'key' => $key,
+                    'foreignKey' => $foreignKey,
+                    'foreignType' => $foreignType,
+                ];
+
+            case Entity::MANY_MANY:
+                $key = $defs->hasKey() ?
+                    $defs->getKey() :
+                    Attribute::ID;
+
+                $foreignKey = $defs->hasForeignKey() ?
+                    $defs->getForeignKey() :
+                    Attribute::ID;
+
+                $nearKey = $defs->hasMidKey() ?
+                    $defs->getMidKey() :
+                    lcfirst($entityType) . 'Id';
+
+                $distantKey = $defs->hasForeignMidKey() ?
+                    $defs->getForeignMidKey() :
+                    lcfirst($defs->getForeignEntityType()) . 'Id';
+
+                return [
+                    'key' => $key,
+                    'foreignKey' => $foreignKey,
+                    'nearKey' => $nearKey,
+                    'distantKey' => $distantKey,
+                ];
+
+            case Entity::BELONGS_TO_PARENT:
+                $key = $relationName . 'Id';
+                $typeKey = $relationName . 'Type';
+
+                return [
+                    'key' => $key,
+                    'typeKey' => $typeKey,
+                    'foreignKey' => Attribute::ID,
+                ];
+        }
+
+        throw new RuntimeException("Relation type '{$type}' not supported for 'getKeys'.");
+    }
+}

application/Espo/ORM/Mapper/Mapper.php

@@ -0,0 +1,83 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Mapper;
+
+use Espo\ORM\Entity;
+use Espo\ORM\Collection;
+use Espo\ORM\Query\Select;
+
+interface Mapper
+{
+    /**
+     * Get a first entity from DB.
+     */
+    public function selectOne(Select $select): ?Entity;
+
+    /**
+     * Select entities from DB.
+     *
+     * @return Collection<Entity>
+     */
+    public function select(Select $select): Collection;
+
+    /**
+     * Get a number of records in DB.
+     */
+    public function count(Select $select): int;
+
+    /**
+     * Insert an entity into DB.
+     */
+    public function insert(Entity $entity): void;
+
+    /**
+     * Insert a collection into DB.
+     *
+     * @param Collection<Entity> $collection
+     */
+    public function massInsert(Collection $collection): void;
+
+    /**
+     * Update an entity in DB.
+     */
+    public function update(Entity $entity): void;
+
+    /**
+     * Delete an entity from DB or mark as deleted.
+     */
+    public function delete(Entity $entity): void;
+
+    /**
+     * Insert an entity into DB, on duplicate key update specified attributes.
+     *
+     * @param string[] $onDuplicateUpdateAttributeList
+     */
+    public function insertOnDuplicateUpdate(Entity $entity, array $onDuplicateUpdateAttributeList): void;
+}

application/Espo/ORM/Mapper/MapperFactory.php

@@ -0,0 +1,35 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Mapper;
+
+interface MapperFactory
+{
+    public function create(string $name): Mapper;
+}

application/Espo/ORM/Mapper/RDBMapper.php

@@ -0,0 +1,117 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Mapper;
+
+use Espo\ORM\Collection;
+use Espo\ORM\Entity;
+use Espo\ORM\Query\Select;
+
+interface RDBMapper extends Mapper
+{
+    /**
+     * Relate an entity with another entity.
+     *
+     * @param Entity $entity An entity.
+     * @param string $relationName A relation name.
+     * @param Entity $foreignEntity A foreign entity.
+     * @param array<string, mixed>|null $columnData Column values.
+     * @return bool True if the row was affected.
+     */
+    public function relate(Entity $entity, string $relationName, Entity $foreignEntity, ?array $columnData): bool;
+
+    /**
+     * Unrelate an entity from another entity.
+     *
+     * @param Entity $entity An entity.
+     * @param string $relationName A relation name.
+     * @param Entity $foreignEntity A foreign entity.
+     */
+    public function unrelate(Entity $entity, string $relationName, Entity $foreignEntity): void;
+
+    /**
+     * Relate an entity from another entity by a given ID.
+     *
+     * @param Entity $entity An entity.
+     * @param string $relationName A relation name.
+     * @param string $id A foreign ID.
+     * @param array<string, mixed>|null $columnData Column values.
+     */
+    public function relateById(Entity $entity, string $relationName, string $id, ?array $columnData = null): bool;
+
+    /**
+     * Unrelate an entity from another entity by a given ID.
+     *
+     * @param Entity $entity An entity.
+     * @param string $relationName A relation name.
+     * @param string $id A foreign ID.
+     */
+    public function unrelateById(Entity $entity, string $relationName, string $id): void;
+
+    /**
+     * Mass relate.
+     */
+    public function massRelate(Entity $entity, string $relationName, Select $select): void;
+
+    /**
+     * Update relationship columns.
+     *
+     * @param array<string, mixed> $columnData
+     */
+    public function updateRelationColumns(
+        Entity $entity,
+        string $relationName,
+        string $id,
+        array $columnData
+    ): void;
+
+    /**
+     * Get a relationship column value.
+     *
+     * @return string|int|float|bool|null A relationship column value.
+     */
+    public function getRelationColumn(
+        Entity $entity,
+        string $relationName,
+        string $id,
+        string $column
+    ): string|int|float|bool|null;
+
+    /**
+     * Select related entities from DB.
+     *
+     * @return Collection<Entity>|Entity|null
+     */
+    public function selectRelated(Entity $entity, string $relationName, ?Select $select = null): Collection|Entity|null;
+
+    /**
+     * Get a number of related entities in DB.
+     */
+    public function countRelated(Entity $entity, string $relationName, ?Select $select = null): int;
+}

application/Espo/ORM/Metadata.php

@@ -0,0 +1,155 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM;
+
+use Espo\ORM\Defs\DefsData;
+
+use InvalidArgumentException;
+
+/**
+ * Metadata.
+ */
+class Metadata
+{
+    /** @var array<string, mixed> */
+    private array $data;
+
+    private Defs $defs;
+    private DefsData $defsData;
+    private EventDispatcher $eventDispatcher;
+
+    public function __construct(
+        private MetadataDataProvider $dataProvider,
+        ?EventDispatcher $eventDispatcher = null
+    ) {
+        $this->data = $dataProvider->get();
+        $this->defsData = new DefsData($this);
+        $this->defs = new Defs($this->defsData);
+        $this->eventDispatcher = $eventDispatcher ?? new EventDispatcher();
+    }
+
+    /**
+     * Update data from the data provider.
+     */
+    public function updateData(): void
+    {
+        $this->data = $this->dataProvider->get();
+
+        $this->defsData->clearCache();
+
+        $this->eventDispatcher->dispatchMetadataUpdate();
+    }
+
+    /**
+     * Get definitions.
+     */
+    public function getDefs(): Defs
+    {
+        return $this->defs;
+    }
+
+    /**
+     * Get a parameter or parameters by key. Key can be a string or array path.
+     *
+     * @param string $entityType An entity type.
+     * @param string[]|string|null $key A Key.
+     * @param mixed $default A default value.
+     * @return mixed
+     */
+    public function get(string $entityType, $key = null, $default = null)
+    {
+        if (!$this->has($entityType)) {
+            return null;
+        }
+
+        $data = $this->data[$entityType];
+
+        if ($key === null) {
+            return $data;
+        }
+
+        return self::getValueByKey($data, $key, $default);
+    }
+
+    /**
+     * Whether an entity type is available.
+     */
+    public function has(string $entityType): bool
+    {
+        return array_key_exists($entityType, $this->data);
+    }
+
+    /**
+     * Get a list of entity types.
+     *
+     * @return string[]
+     */
+    public function getEntityTypeList(): array
+    {
+        return array_keys($this->data);
+    }
+
+    /**
+     * @param array<string, mixed> $data
+     * @param string[]|string|null $key
+     * @param mixed $default A default value.
+     * @return mixed
+     */
+    private static function getValueByKey(array $data, $key = null, $default = null)
+    {
+        if (!is_string($key) && !is_array($key) && !is_null($key)) { /** @phpstan-ignore-line */
+            throw new InvalidArgumentException();
+        }
+
+        if (is_null($key) || empty($key)) {
+            return $data;
+        }
+
+        $path = $key;
+
+        if (is_string($key)) {
+            $path = explode('.', $key);
+        }
+
+        /** @var string[] $path */
+
+        $item = $data;
+
+        foreach ($path as $k) {
+            if (!array_key_exists($k, $item)) {
+                return $default;
+            }
+
+            $item = $item[$k];
+        }
+
+        return $item;
+    }
+}

application/Espo/ORM/MetadataDataProvider.php

@@ -0,0 +1,41 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM;
+
+/**
+ * Provides data for metadata.
+ */
+interface MetadataDataProvider
+{
+    /**
+     * @return array<string, mixed>
+     */
+    public function get(): array;
+}

application/Espo/ORM/Name/Attribute.php

@@ -0,0 +1,36 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Name;
+
+interface Attribute
+{
+    public const ID = 'id';
+    public const DELETED = 'deleted';
+}

application/Espo/ORM/PDO/DefaultPDOProvider.php

@@ -0,0 +1,59 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\PDO;
+
+use Espo\ORM\DatabaseParams;
+use PDO;
+
+class DefaultPDOProvider implements PDOProvider
+{
+    private ?PDO $pdo = null;
+
+    public function __construct(
+        private DatabaseParams $databaseParams,
+        private PDOFactory $pdoFactory
+    ) {}
+
+    public function get(): PDO
+    {
+        if (!$this->pdo) {
+            $this->intPDO();
+        }
+
+        assert($this->pdo !== null);
+
+        return $this->pdo;
+    }
+
+    private function intPDO(): void
+    {
+        $this->pdo = $this->pdoFactory->create($this->databaseParams);
+    }
+}

application/Espo/ORM/PDO/MysqlPDOFactory.php

@@ -0,0 +1,79 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\PDO;
+
+use Espo\ORM\DatabaseParams;
+use PDO;
+use RuntimeException;
+
+class MysqlPDOFactory implements PDOFactory
+{
+    private const DEFAULT_CHARSET = 'utf8mb4';
+
+    public function create(DatabaseParams $databaseParams): PDO
+    {
+        $platform = strtolower($databaseParams->getPlatform() ?? '');
+
+        $host = $databaseParams->getHost();
+        $port = $databaseParams->getPort();
+        $dbname = $databaseParams->getName();
+        $charset = $databaseParams->getCharset() ?? self::DEFAULT_CHARSET;
+        $username = $databaseParams->getUsername();
+        $password = $databaseParams->getPassword();
+
+        if (!$platform) {
+            throw new RuntimeException("No 'platform' parameter.");
+        }
+
+        if (!$host) {
+            throw new RuntimeException("No 'host' parameter.");
+        }
+
+        $dsn = $platform . ':' . 'host=' . $host;
+
+        if ($port) {
+            $dsn .= ';' . 'port=' . (string) $port;
+        }
+
+        if ($dbname) {
+            $dsn .= ';' . 'dbname=' . $dbname;
+        }
+
+        $dsn .= ';' . 'charset=' . $charset;
+
+        $options = Options::getOptionsFromDatabaseParams($databaseParams);
+
+        $pdo = new PDO($dsn, $username, $password, $options);
+
+        $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+
+        return $pdo;
+    }
+}

application/Espo/ORM/PDO/Options.php

@@ -0,0 +1,71 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\PDO;
+
+use Espo\ORM\DatabaseParams;
+
+use PDO;
+
+class Options
+{
+    /**
+     * @return array<int, mixed>
+     */
+    public static function getOptionsFromDatabaseParams(DatabaseParams $databaseParams): array
+    {
+        $options = [];
+
+        if ($databaseParams->getSslCa()) {
+            $options[PDO::MYSQL_ATTR_SSL_CA] = $databaseParams->getSslCa();
+        }
+
+        if ($databaseParams->getSslCert()) {
+            $options[PDO::MYSQL_ATTR_SSL_CERT] = $databaseParams->getSslCert();
+        }
+
+        if ($databaseParams->getSslKey()) {
+            $options[PDO::MYSQL_ATTR_SSL_KEY] = $databaseParams->getSslKey();
+        }
+
+        if ($databaseParams->getSslCaPath()) {
+            $options[PDO::MYSQL_ATTR_SSL_CAPATH] = $databaseParams->getSslCaPath();
+        }
+
+        if ($databaseParams->getSslCipher()) {
+            $options[PDO::MYSQL_ATTR_SSL_CIPHER] = $databaseParams->getSslCipher();
+        }
+
+        if ($databaseParams->isSslVerifyDisabled()) {
+            $options[PDO::MYSQL_ATTR_SSL_VERIFY_SERVER_CERT] = false;
+        }
+
+        return $options;
+    }
+}

application/Espo/ORM/PDO/PDOFactory.php

@@ -0,0 +1,38 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\PDO;
+
+use Espo\ORM\DatabaseParams;
+use PDO;
+
+interface PDOFactory
+{
+    public function create(DatabaseParams $databaseParams): PDO;
+}

application/Espo/ORM/PDO/PDOProvider.php

@@ -0,0 +1,37 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\PDO;
+
+use PDO;
+
+interface PDOProvider
+{
+    public function get(): PDO;
+}

application/Espo/ORM/PDO/PostgresqlPDOFactory.php

@@ -0,0 +1,81 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\PDO;
+
+use Espo\ORM\DatabaseParams;
+use PDO;
+use RuntimeException;
+
+class PostgresqlPDOFactory implements PDOFactory
+{
+    private const DEFAULT_CHARSET = 'utf8';
+
+    public function create(DatabaseParams $databaseParams): PDO
+    {
+        $platform = strtolower($databaseParams->getPlatform() ?? '');
+
+        $host = $databaseParams->getHost();
+        $port = $databaseParams->getPort();
+        $dbname = $databaseParams->getName();
+        $charset = $databaseParams->getCharset() ?? self::DEFAULT_CHARSET;
+        $username = $databaseParams->getUsername();
+        $password = $databaseParams->getPassword();
+
+        if (!$platform) {
+            throw new RuntimeException("No 'platform' parameter.");
+        }
+
+        if (!$host) {
+            throw new RuntimeException("No 'host' parameter.");
+        }
+
+        $dsn = 'pgsql:' . 'host=' . $host;
+
+        if ($port) {
+            $dsn .= ';' . 'port=' . (string) $port;
+        }
+
+        if ($dbname) {
+            $dsn .= ';' . 'dbname=' . $dbname;
+        }
+
+        $dsn .= ';' . 'options=' . "'--client_encoding={$charset}'";
+
+        $options = Options::getOptionsFromDatabaseParams($databaseParams);
+
+        $pdo = new PDO($dsn, $username, $password, $options);
+
+        $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+
+        $pdo->query("SET time zone 'UTC'");
+
+        return $pdo;
+    }
+}

application/Espo/ORM/Query/BaseBuilderTrait.php

@@ -0,0 +1,60 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use RuntimeException;
+
+trait BaseBuilderTrait
+{
+    /**
+     * Must be protected for compatibility reasons.
+     *
+     * @var array<string, mixed>
+     */
+    protected $params = [];
+
+    public function __construct()
+    {
+    }
+
+    private function isEmpty(): bool
+    {
+        return empty($this->params);
+    }
+
+    private function cloneInternal(Query $query): void
+    {
+        if (!$this->isEmpty()) {
+            throw new RuntimeException("Clone can be called only on a new empty builder instance.");
+        }
+
+        $this->params = $query->getRaw();
+    }
+}

application/Espo/ORM/Query/BaseTrait.php

@@ -0,0 +1,70 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+trait BaseTrait
+{
+    /**
+     * @var array<string, mixed>
+     */
+    private $params = [];
+
+    /**
+     * Get parameters in RAW format.
+     *
+     * @return array<string, mixed>
+     */
+    public function getRaw(): array
+    {
+        return $this->params;
+    }
+
+    /**
+     * Create from RAW params.
+     *
+     * @param array<string, mixed> $params
+     */
+    public static function fromRaw(array $params): self
+    {
+        $obj = new self();
+
+        $obj->validateRawParams($params);
+
+        $obj->params = $params;
+
+        return $obj;
+    }
+
+    /**
+     * @param array<string, mixed> $params
+     */
+    private function validateRawParams(array $params): void
+    {}
+}

application/Espo/ORM/Query/Builder.php

@@ -0,0 +1,42 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+/**
+ * Builds query parameters.
+ * Builder instances are one-off, meaning that you need to instantiate it for every new building process.
+ */
+interface Builder
+{
+    /**
+     * Build a query instance.
+     */
+    public function build(): Query;
+}

application/Espo/ORM/Query/Delete.php

@@ -0,0 +1,81 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use RuntimeException;
+
+/**
+ * Delete parameters.
+ *
+ * Immutable.
+ */
+class Delete implements Query
+{
+    use SelectingTrait;
+    use BaseTrait;
+
+    /**
+     * Get an entity type.
+     */
+    public function getFrom(): string
+    {
+        return $this->params['from'];
+    }
+
+    /**
+     * Get a from-alias
+     */
+    public function getFromAlias(): ?string
+    {
+        return $this->params['fromAlias'] ?? null;
+    }
+
+    /**
+     * Get a LIMIT.
+     */
+    public function getLimit(): ?int
+    {
+        return $this->params['limit'] ?? null;
+    }
+
+    /**
+     * @param array<string, mixed> $params
+     */
+    private function validateRawParams(array $params): void
+    {
+        $this->validateRawParamsSelecting($params);
+
+        $from = $params['from'] ?? null;
+
+        if (!$from || !is_string($from)) {
+            throw new RuntimeException("Select params: Missing 'from'.");
+        }
+    }
+}

application/Espo/ORM/Query/DeleteBuilder.php

@@ -0,0 +1,88 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use RuntimeException;
+
+class DeleteBuilder implements Builder
+{
+    use SelectingBuilderTrait;
+
+    /**
+     * Create an instance.
+     */
+    public static function create(): self
+    {
+        return new self();
+    }
+
+    /**
+     * Build a DELETE query.
+     */
+    public function build(): Delete
+    {
+        return Delete::fromRaw($this->params);
+    }
+
+    /**
+     * Clone an existing query for a subsequent modifying and building.
+     */
+    public function clone(Delete $query): self
+    {
+        $this->cloneInternal($query);
+
+        return $this;
+    }
+
+    /**
+     * Set FROM parameter. For what entity type to build a query.
+     */
+    public function from(string $entityType, ?string $alias = null): self
+    {
+        if (isset($this->params['from'])) {
+            throw new RuntimeException("Method 'from' can be called only once.");
+        }
+
+        $this->params['from'] = $entityType;
+        $this->params['fromAlias'] = $alias;
+
+        return $this;
+    }
+
+    /**
+     * Apply LIMIT.
+     */
+    public function limit(?int $limit = null): self
+    {
+        $this->params['limit'] = $limit;
+
+        return $this;
+    }
+}

application/Espo/ORM/Query/Insert.php

@@ -0,0 +1,72 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use RuntimeException;
+
+/**
+ * Insert parameters.
+ *
+ * Immutable.
+ */
+class Insert implements Query
+{
+    use BaseTrait;
+
+    /**
+     * @param array<string, mixed> $params
+     */
+    private function validateRawParams(array $params): void
+    {
+        $into = $params['into'] ?? null;
+
+        if (!$into || !is_string($into)) {
+            throw new RuntimeException("Bad or missing 'into' parameter.");
+        }
+
+        $columns = $params['columns'] ?? [];
+
+        if (!is_array($columns)) {
+            throw new RuntimeException("Bad 'columns' parameter.");
+        }
+
+        $values = $params['values'] ?? [];
+
+        if (!is_array($values)) {
+            throw new RuntimeException("Bad 'values' parameter.");
+        }
+
+        $updateSet = $params['updateSet'] ?? null;
+
+        if ($updateSet && !is_array($updateSet)) {
+            throw new RuntimeException("Bad 'updateSet' parameter.");
+        }
+    }
+}

application/Espo/ORM/Query/InsertBuilder.php

@@ -0,0 +1,122 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+class InsertBuilder implements Builder
+{
+    use BaseBuilderTrait;
+
+    /**
+     * @var array<string, mixed>
+     */
+    protected $params = [];
+
+    /**
+     * Create an instance.
+     */
+    public static function create(): self
+    {
+        return new self();
+    }
+
+    /**
+     * Build a INSERT query.
+     */
+    public function build(): Insert
+    {
+        return Insert::fromRaw($this->params);
+    }
+
+    /**
+     * Clone an existing query for a subsequent modifying and building.
+     */
+    public function clone(Insert $query): self
+    {
+        $this->cloneInternal($query);
+
+        return $this;
+    }
+
+    /**
+     * Into what entity type to insert.
+     */
+    public function into(string $entityType): self
+    {
+        $this->params['into'] = $entityType;
+
+        return $this;
+    }
+
+    /**
+     * What columns to set with values. A list of columns.
+     *
+     * @param string[] $columns
+     */
+    public function columns(array $columns): self
+    {
+        $this->params['columns'] = $columns;
+
+        return $this;
+    }
+
+    /**
+     * What values to insert. A key-value map or a list of key-value maps.
+     *
+     * @param array<string, ?scalar>|array<string, ?scalar>[] $values
+     */
+    public function values(array $values): self
+    {
+        $this->params['values'] = $values;
+
+        return $this;
+    }
+
+    /**
+     * Values to set on duplicate key. A key-value map.
+     *
+     * @param array<string, ?scalar> $updateSet
+     */
+    public function updateSet(array $updateSet): self
+    {
+        $this->params['updateSet'] = $updateSet;
+
+        return $this;
+    }
+
+    /**
+     * For a mass insert by a select sub-query.
+     */
+    public function valuesQuery(SelectingQuery $query): self
+    {
+        $this->params['valuesQuery'] = $query;
+
+        return $this;
+    }
+}

application/Espo/ORM/Query/LockTable.php

@@ -0,0 +1,59 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use RuntimeException;
+
+/**
+ * LOCK TABLE parameters.
+ *
+ * Immutable.
+ */
+class LockTable implements Query
+{
+    use BaseTrait;
+
+    public const MODE_SHARE = 'SHARE';
+    public const MODE_EXCLUSIVE = 'EXCLUSIVE';
+
+    /**
+     * @param array<string, mixed> $params
+     */
+    protected function validateRawParams(array $params): void
+    {
+        if (empty($params['table'])) {
+            throw new RuntimeException("LockTable params: No table specified.");
+        }
+
+        if (empty($params['mode'])) {
+            throw new RuntimeException("LockTable params: No mode specified.");
+        }
+    }
+}

application/Espo/ORM/Query/LockTableBuilder.php

@@ -0,0 +1,91 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+class LockTableBuilder implements Builder
+{
+    use BaseBuilderTrait;
+
+    /**
+     * Create an instance.
+     */
+    public static function create(): self
+    {
+        return new self();
+    }
+
+    /**
+     * Build a LOCK TABLE query.
+     */
+    public function build(): LockTable
+    {
+        return LockTable::fromRaw($this->params);
+    }
+
+    /**
+     * Clone an existing query for a subsequent modifying and building.
+     */
+    public function clone(LockTable $query): self
+    {
+        $this->cloneInternal($query);
+
+        return $this;
+    }
+
+    /**
+     * What entity type to lock.
+     */
+    public function table(string $entityType): self
+    {
+        $this->params['table'] = $entityType;
+
+        return $this;
+    }
+
+    /**
+     * In SHARE mode.
+     */
+    public function inShareMode(): self
+    {
+        $this->params['mode'] = LockTable::MODE_SHARE;
+
+        return $this;
+    }
+
+    /**
+     * In EXCLUSIVE mode.
+     */
+    public function inExclusiveMode(): self
+    {
+        $this->params['mode'] = LockTable::MODE_EXCLUSIVE;
+
+        return $this;
+    }
+}

application/Espo/ORM/Query/Part/Condition.php

@@ -0,0 +1,217 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part;
+
+use Espo\ORM\Query\Part\Where\AndGroup;
+use Espo\ORM\Query\Part\Where\Comparison;
+use Espo\ORM\Query\Part\Where\Exists;
+use Espo\ORM\Query\Part\Where\Not;
+use Espo\ORM\Query\Part\Where\OrGroup;
+
+use Espo\ORM\Query\Select;
+
+/**
+ * A util-class for creating items that can be used as a where-clause.
+ */
+class Condition
+{
+    private function __construct()
+    {}
+
+    /**
+     * Create 'AND' group.
+     */
+    public static function and(WhereItem ...$items): AndGroup
+    {
+        return AndGroup::create(...$items);
+    }
+
+    /**
+     * Create 'OR' group.
+     */
+    public static function or(WhereItem ...$items): OrGroup
+    {
+        return OrGroup::create(...$items);
+    }
+
+    /**
+     * Create 'NOT'.
+     */
+    public static function not(WhereItem $item): Not
+    {
+        return Not::create($item);
+    }
+
+    /**
+     * Create `EXISTS`.
+     */
+    public static function exists(Select $subQuery): Exists
+    {
+        return Exists::create($subQuery);
+    }
+
+    /**
+     * Create a column reference expression.
+     *
+     * @param string $expression Examples: `columnName`, `alias.columnName`.
+     */
+    public static function column(string $expression): Expression
+    {
+        return Expression::column($expression);
+    }
+
+    /**
+     * Create '=' comparison.
+     *
+     * @param Expression $argument1 An expression.
+     * @param Expression|Select|string|int|float|bool|null $argument2 A scalar, expression or sub-query.
+     */
+    public static function equal(
+        Expression $argument1,
+        Expression|Select|string|int|float|bool|null $argument2
+    ): Comparison {
+
+        return Comparison::equal($argument1, $argument2);
+    }
+
+    /**
+     * Create '!=' comparison.
+     *
+     * @param Expression $argument1 An expression.
+     * @param Expression|Select|string|int|float|bool|null $argument2 A scalar, expression or sub-query.
+     */
+    public static function notEqual(
+        Expression $argument1,
+        Expression|Select|string|int|float|bool|null $argument2
+    ): Comparison {
+
+        return Comparison::notEqual($argument1, $argument2);
+    }
+
+    /**
+     * Create 'LIKE' comparison.
+     *
+     * @param Expression $subject What to test.
+     * @param Expression|string $pattern A pattern.
+     */
+    public static function like(Expression $subject, Expression|string $pattern): Comparison
+    {
+        return Comparison::like($subject, $pattern);
+    }
+
+    /**
+     * Create 'NOT LIKE' comparison.
+     *
+     * @param Expression $subject What to test.
+     * @param Expression|string $pattern A pattern.
+     */
+    public static function notLike(Expression $subject, Expression|string $pattern): Comparison
+    {
+        return Comparison::notLike($subject, $pattern);
+    }
+
+    /**
+     * Create '>' comparison.
+     *
+     * @param Expression $argument1 An expression.
+     * @param Expression|Select|string|int|float $argument2 A scalar, expression or sub-query.
+     */
+    public static function greater(
+        Expression $argument1,
+        Expression|Select|string|int|float $argument2
+    ): Comparison {
+
+        return Comparison::greater($argument1, $argument2);
+    }
+
+    /**
+     * Create '>=' comparison.
+     *
+     * @param Expression $argument1 An expression.
+     * @param Expression|Select|string|int|float $argument2 A scalar, expression or sub-query.
+     */
+    public static function greaterOrEqual(
+        Expression $argument1,
+        Expression|Select|string|int|float $argument2
+    ): Comparison {
+
+        return Comparison::greaterOrEqual($argument1, $argument2);
+    }
+
+    /**
+     * Create '<' comparison.
+     *
+     * @param Expression $argument1 An expression.
+     * @param Expression|Select|string|int|float $argument2 A scalar, expression or sub-query.
+     */
+    public static function less(
+        Expression $argument1,
+        Expression|Select|string|int|float $argument2
+    ): Comparison {
+
+        return Comparison::less($argument1, $argument2);
+    }
+
+    /**
+     * Create '<=' comparison.
+     *
+     * @param Expression $argument1 An expression.
+     * @param Expression|Select|string|int|float $argument2 A scalar, expression or sub-query.
+     */
+    public static function lessOrEqual(
+        Expression $argument1,
+        Expression|Select|string|int|float $argument2
+    ): Comparison {
+
+        return Comparison::lessOrEqual($argument1, $argument2);
+    }
+
+    /**
+     * Create 'IN' comparison.
+     *
+     * @param Expression $subject What to test.
+     * @param Select|scalar[] $set A set of values. A select query or array of scalars.
+     */
+    public static function in(Expression $subject, Select|array $set): Comparison
+    {
+        return Comparison::in($subject, $set);
+    }
+
+    /**
+     * Create 'NOT IN' comparison.
+     *
+     * @param Expression $subject What to test.
+     * @param Select|scalar[] $set A set of values. A select query or array of scalars.
+     */
+    public static function notIn(Expression $subject, Select|array $set): Comparison
+    {
+        return Comparison::notIn($subject, $set);
+    }
+}

application/Espo/ORM/Query/Part/Expression.php

@@ -0,0 +1,820 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part;
+
+use Espo\ORM\Query\Part\Expression\Util;
+
+use RuntimeException;
+
+/**
+ * A complex expression. Can be a function or a simple column reference. Immutable.
+ */
+class Expression implements WhereItem
+{
+    private string $expression;
+
+    public function __construct(string $expression)
+    {
+        if ($expression === '') {
+            throw new RuntimeException("Expression can't be empty.");
+        }
+
+        if (str_ends_with($expression, ':')) {
+            throw new RuntimeException("Expression should not end with `:`.");
+        }
+
+        $this->expression = $expression;
+    }
+
+    public function getRaw(): array
+    {
+        return [$this->getRawKey() => null];
+    }
+
+    public function getRawKey(): string
+    {
+        return $this->expression . ':';
+    }
+
+    public function getRawValue(): mixed
+    {
+        return null;
+    }
+
+    /**
+     * Get a string expression.
+     */
+    public function getValue(): string
+    {
+        return $this->expression;
+    }
+
+    /**
+     * Create an expression from a string.
+     */
+    public static function create(string $expression): self
+    {
+        return new self($expression);
+    }
+
+    /**
+     * Create an expression from a scalar value or NULL.
+     *
+     * @param string|float|int|bool|null $value A scalar or NULL.
+     */
+    public static function value(string|float|int|bool|null $value): self
+    {
+        return self::create(self::stringifyArgument($value));
+    }
+
+    /**
+     * Create a column reference expression.
+     *
+     * @param string $expression Examples: `columnName`, `alias.columnName`.
+     */
+    public static function column(string $expression): self
+    {
+        $string = $expression;
+
+        if (strlen($string) && $string[0] === '@') {
+            $string = substr($string, 1);
+        }
+
+        if ($string === '') {
+            throw new RuntimeException("Empty column.");
+        }
+
+        if (!preg_match('/^[a-zA-Z\d.]+$/', $string)) {
+            throw new RuntimeException("Bad column. Must be of letters, digits. Can have a dot.");
+        }
+
+        return self::create($expression);
+    }
+
+    /**
+     * Create an alias reference expression.
+     *
+     * @param string $expression Examples: `someAlias`, `subQueryAlias.someAlias`.
+     * @since 8.1.0
+     */
+    public static function alias(string $expression): self
+    {
+        if ($expression === '') {
+            throw new RuntimeException("Empty alias.");
+        }
+
+        if (!preg_match('/^[a-zA-Z\d.]+$/', $expression)) {
+            throw new RuntimeException("Bad alias expression. Must be of letters, digits. Can have a dot.");
+        }
+
+        if (str_contains($expression, '.')) {
+            [$left, $right] = explode('.', $expression, 2);
+
+            return self::create($left . '.#' . $right);
+        }
+
+        return self::create('#' . $expression);
+    }
+
+    /**
+     * 'COUNT' function.
+     *
+     * @param Expression $expression
+     */
+    public static function count(Expression $expression): self
+    {
+        return self::composeFunction('COUNT', $expression);
+    }
+
+    /**
+     * 'MIN' function.
+     *
+     * @param Expression $expression
+     */
+    public static function min(Expression $expression): self
+    {
+        return self::composeFunction('MIN', $expression);
+    }
+
+    /**
+     * 'MAX' function.
+     *
+     * @param Expression $expression
+     */
+    public static function max(Expression $expression): self
+    {
+        return self::composeFunction('MAX', $expression);
+    }
+
+    /**
+     * 'SUM' function.
+     *
+     * @param Expression $expression
+     */
+    public static function sum(Expression $expression): self
+    {
+        return self::composeFunction('SUM', $expression);
+    }
+
+    /**
+     * 'AVG' function.
+     *
+     * @param Expression $expression
+     */
+    public static function average(Expression $expression): self
+    {
+        return self::composeFunction('AVG', $expression);
+    }
+
+    /**
+     * 'IF' function. Return $then if a condition is true, $else otherwise.
+     *
+     * @param Expression $condition A condition.
+     * @param Expression|string|int|float|bool|null $then Then.
+     * @param Expression|string|int|float|bool|null $else Else.
+     */
+    public static function if(
+        Expression $condition,
+        Expression|string|int|float|bool|null $then,
+        Expression|string|int|float|bool|null $else
+    ): self {
+
+        return self::composeFunction('IF', $condition, $then, $else);
+    }
+
+    /**
+     * 'CASE' expression. Even arguments define 'WHEN' conditions, following odd arguments
+     * define 'THEN' values. The last unmatched argument defines the 'ELSE' value.
+     *
+     * @param Expression|scalar|null ...$arguments Arguments.
+     */
+    public static function switch(Expression|string|int|float|bool|null ...$arguments): self
+    {
+        if (count($arguments) < 2) {
+            throw new RuntimeException("Too few arguments.");
+        }
+
+        return self::composeFunction('SWITCH', ...$arguments);
+    }
+
+    /**
+     * 'CASE' expression that maps keys to values. The first argument is the value to map.
+     * Odd arguments define keys, the following even arguments define mapped values.
+     * The last unmatched argument defines the 'ELSE' value.
+     *
+     * @param Expression|scalar|null ...$arguments Arguments.
+     */
+    public static function map(Expression|string|int|float|bool|null ...$arguments): self
+    {
+        if (count($arguments) < 3) {
+            throw new RuntimeException("Too few arguments.");
+        }
+
+        return self::composeFunction('MAP', ...$arguments);
+    }
+
+    /**
+     * 'IFNULL' function. If the first argument is not NULL, returns it,
+     * otherwise returns the second argument.
+     *
+     * @param Expression $value A value.
+     * @param Expression|string|int|float|bool $fallbackValue A fallback value.
+     */
+    public static function ifNull(Expression $value, Expression|string|int|float|bool $fallbackValue): self
+    {
+        return self::composeFunction('IFNULL', $value, $fallbackValue);
+    }
+
+    /**
+     * 'NULLIF' function. If $arg1 = $arg2, returns NULL,
+     * otherwise returns the first argument.
+     *
+     * @param Expression|string|int|float|bool $argument1
+     * @param Expression|string|int|float|bool $argument2
+     */
+    public static function nullIf(
+        Expression|string|int|float|bool $argument1,
+        Expression|string|int|float|bool $argument2
+    ): self {
+
+        return self::composeFunction('NULLIF', $argument1, $argument2);
+    }
+
+    /**
+     * 'LIKE' operator.
+     *
+     * Example: `like(Expression:column('test'), 'test%'`.
+     *
+     * @param Expression $subject A subject.
+     * @param Expression|string $pattern A pattern.
+     */
+    public static function like(Expression $subject, Expression|string $pattern): self
+    {
+        return self::composeFunction('LIKE', $subject, $pattern);
+    }
+
+    /**
+     * '=' operator.
+     *
+     * @param Expression|string|int|float|bool $argument1
+     * @param Expression|string|int|float|bool $argument2
+     */
+    public static function equal(
+        Expression|string|int|float|bool $argument1,
+        Expression|string|int|float|bool $argument2
+    ): self {
+
+        return self::composeFunction('EQUAL', $argument1, $argument2);
+    }
+
+    /**
+     * '<>' operator.
+     *
+     * @param Expression|string|int|float|bool $argument1
+     * @param Expression|string|int|float|bool $argument2
+     */
+    public static function notEqual(
+        Expression|string|int|float|bool $argument1,
+        Expression|string|int|float|bool $argument2
+    ): self {
+
+        return self::composeFunction('NOT_EQUAL', $argument1, $argument2);
+    }
+
+    /**
+     * '>' operator.
+     *
+     * @param Expression|string|int|float|bool $argument1
+     * @param Expression|string|int|float|bool $argument2
+     */
+    public static function greater(
+        Expression|string|int|float|bool $argument1,
+        Expression|string|int|float|bool $argument2
+    ): self {
+
+        return self::composeFunction('GREATER_THAN', $argument1, $argument2);
+    }
+
+    /**
+     * '<' operator.
+     *
+     * @param Expression|string|int|float|bool $argument1
+     * @param Expression|string|int|float|bool $argument2
+     */
+    public static function less(
+        Expression|string|int|float|bool $argument1,
+        Expression|string|int|float|bool $argument2
+    ): self {
+
+        return self::composeFunction('LESS_THAN', $argument1, $argument2);
+    }
+
+    /**
+     * '>=' operator.
+     *
+     * @param Expression|string|int|float|bool $argument1
+     * @param Expression|string|int|float|bool $argument2
+     */
+    public static function greaterOrEqual(
+        Expression|string|int|float|bool $argument1,
+        Expression|string|int|float|bool $argument2
+    ): self {
+
+        return self::composeFunction('GREATER_THAN_OR_EQUAL', $argument1, $argument2);
+    }
+
+    /**
+     * '<=' operator.
+     *
+     * @param Expression|string|int|float|bool $argument1
+     * @param Expression|string|int|float|bool $argument2
+     */
+    public static function lessOrEqual(
+        Expression|string|int|float|bool $argument1,
+        Expression|string|int|float|bool $argument2
+    ): self {
+
+        return self::composeFunction('LESS_THAN_OR_EQUAL', $argument1, $argument2);
+    }
+
+    /**
+     * 'IS NULL' operator.
+     *
+     * @param Expression $expression
+     */
+    public static function isNull(Expression $expression): self
+    {
+        return self::composeFunction('IS_NULL', $expression);
+    }
+
+    /**
+     * 'IS NOT NULL' operator.
+     *
+     * @param Expression $expression
+     */
+    public static function isNotNull(Expression $expression): self
+    {
+        return self::composeFunction('IS_NOT_NULL', $expression);
+    }
+
+    /**
+     * 'IN' operator. Check whether a value is within a set of values.
+     *
+     * @param Expression $expression
+     * @param Expression[]|string[]|int[]|float[]|bool[] $values
+     */
+    public static function in(Expression $expression, array $values): self
+    {
+        return self::composeFunction('IN', $expression, ...$values);
+    }
+
+    /**
+     * 'NOT IN' operator. Check whether a value is not within a set of values.
+     *
+     * @param Expression $expression
+     * @param Expression[]|string[]|int[]|float[]|bool[] $values
+     */
+    public static function notIn(Expression $expression, array $values): self
+    {
+        return self::composeFunction('NOT_IN', $expression, ...$values);
+    }
+
+    /**
+     * 'COALESCE' function. Returns the first non-NULL value in the list.
+     */
+    public static function coalesce(Expression ...$expressions): self
+    {
+        return self::composeFunction('COALESCE', ...$expressions);
+    }
+
+    /**
+     * 'MONTH' function. Returns a month number of a passed date or date-time.
+     *
+     * @param Expression $date
+     */
+    public static function month(Expression $date): self
+    {
+        return self::composeFunction('MONTH_NUMBER', $date);
+    }
+
+    /**
+     * 'WEEK' function. Returns a week number of a passed date or date-time.
+     *
+     * @param Expression $date
+     * @param int $weekStart A week start. `0` for Sunday, `1` for Monday.
+     */
+    public static function week(Expression $date, int $weekStart = 0): self
+    {
+        if ($weekStart !== 0 && $weekStart !== 1) {
+            throw new RuntimeException("Week start can be only 0 or 1.");
+        }
+
+        if ($weekStart === 1) {
+            return self::composeFunction('WEEK_NUMBER_1', $date);
+        }
+
+        return self::composeFunction('WEEK_NUMBER', $date);
+    }
+
+    /**
+     * 'DAYOFWEEK' function. A day of week of a passed date or date-time. 1..7.
+     *
+     * @param Expression $date
+     */
+    public static function dayOfWeek(Expression $date): self
+    {
+        return self::composeFunction('DAYOFWEEK', $date);
+    }
+
+    /**
+     * 'DAYOFMONTH' function. A day of month of a passed date or date-time. 1..31.
+     *
+     * @param Expression $date
+     */
+    public static function dayOfMonth(Expression $date): self
+    {
+        return self::composeFunction('DAYOFMONTH', $date);
+    }
+
+    /**
+     * 'YEAR' function. A year number of a passed date or date-time.
+     *
+     * @param Expression $date
+     */
+    public static function year(Expression $date): self
+    {
+        return self::composeFunction('YEAR', $date);
+    }
+
+    /**
+     * 'YEAR' function taking into account a fiscal year start.
+     *
+     * @param Expression $date
+     * @param int $fiscalYearStart A month number of a fiscal year start. 1..12.
+     */
+    public static function yearFiscal(Expression $date, int $fiscalYearStart = 1): self
+    {
+        if ($fiscalYearStart < 1 || $fiscalYearStart > 12) {
+            throw new RuntimeException("Bad fiscal year start.");
+        }
+
+        return self::composeFunction('YEAR_' . strval($fiscalYearStart), $date);
+    }
+
+    /**
+     * 'QUARTER' function. A quarter number of a passed date or date-time. 1..4.
+     *
+     * @param Expression $date
+     */
+    public static function quarter(Expression $date): self
+    {
+        return self::composeFunction('QUARTER_NUMBER', $date);
+    }
+
+    /**
+     * 'HOUR' function. A hour number of a passed date-time. 0..23.
+     *
+     * @param Expression $dateTime
+     */
+    public static function hour(Expression $dateTime): self
+    {
+        return self::composeFunction('HOUR', $dateTime);
+    }
+
+    /**
+     * 'MINUTE' function. A minute number of a passed date-time. 0..59.
+     *
+     * @param Expression $dateTime
+     */
+    public static function minute(Expression $dateTime): self
+    {
+        return self::composeFunction('MINUTE', $dateTime);
+    }
+
+    /**
+     * 'SECOND' function. A second number of a passed date-time. 0..59.
+     *
+     * @param Expression $dateTime
+     */
+    public static function second(Expression $dateTime): self
+    {
+        return self::composeFunction('SECOND', $dateTime);
+    }
+
+    /**
+     * 'UNIX_TIMESTAMP' function. Seconds.
+     *
+     * @param Expression $dateTime
+     * @since 9.0.0
+     */
+    public static function unixTimestamp(Expression $dateTime): self
+    {
+        return self::composeFunction('UNIX_TIMESTAMP', $dateTime);
+    }
+
+    /**
+     * 'NOW' function. A current date and time.
+     */
+    public static function now(): self
+    {
+        return self::composeFunction('NOW');
+    }
+
+    /**
+     * 'DATE' function. Returns a date part of a date-time.
+     *
+     * @param Expression $dateTime
+     */
+    public static function date(Expression $dateTime): self
+    {
+        return self::composeFunction('DATE', $dateTime);
+    }
+
+    /**
+     * Time zone conversion function. Converts a passed data-time applying a hour offset.
+     *
+     * @param Expression $date
+     */
+    public static function convertTimezone(Expression $date, float $offset): self
+    {
+        return self::composeFunction('TZ', $date, $offset);
+    }
+
+    /**
+     * 'CONCAT' function. Concatenates multiple strings.
+     *
+     * @param Expression|string ...$strings Strings.
+     */
+    public static function concat(Expression|string ...$strings): self
+    {
+        return self::composeFunction('CONCAT', ...$strings);
+    }
+
+    /**
+     * 'LEFT' function. Returns a specified number of characters from the left of a string.
+     */
+    public static function left(Expression $string, int $offset): self
+    {
+        return self::composeFunction('LEFT', $string, $offset);
+    }
+
+    /**
+     * 'LOWER' function. Converts a string to a lower case.
+     */
+    public static function lowerCase(Expression $string): self
+    {
+        return self::composeFunction('LOWER', $string);
+    }
+
+    /**
+     * 'UPPER' function. Converts a string to an upper case.
+     */
+    public static function upperCase(Expression $string): self
+    {
+        return self::composeFunction('UPPER', $string);
+    }
+
+    /**
+     * 'TRIM' function. Removes leading and trailing spaces.
+     */
+    public static function trim(Expression $string): self
+    {
+        return self::composeFunction('TRIM', $string);
+    }
+
+    /**
+     * 'BINARY' function. Converts a string value to a binary string.
+     */
+    public static function binary(Expression $string): self
+    {
+        return self::composeFunction('BINARY', $string);
+    }
+
+    /**
+     * 'CHAR_LENGTH' function. A number of characters in a string.
+     */
+    public static function charLength(Expression $string): self
+    {
+        return self::composeFunction('CHAR_LENGTH', $string);
+    }
+
+    /**
+     * 'REPLACE' function. Replaces all the occurrences of a sub-string within a string.
+     *
+     * @param Expression $haystack A subject.
+     * @param Expression|string $needle A string to be replaced.
+     * @param Expression|string $replaceWith A string to replace with.
+     */
+    public static function replace(
+        Expression $haystack,
+        Expression|string $needle,
+        Expression|string $replaceWith
+    ): self {
+
+        return self::composeFunction('REPLACE', $haystack, $needle, $replaceWith);
+    }
+
+    /**
+     * 'FIELD' operator (in MySQL). Returns an index (position) of an expression
+     * in a list. Returns `0` if not found. The first index is `1`.
+     *
+     * @param Expression $expression
+     * @param Expression[]|string[]|int[]|float[] $list
+     */
+    public static function positionInList(Expression $expression, array $list): self
+    {
+        return self::composeFunction('POSITION_IN_LIST', $expression, ...$list);
+    }
+
+    /**
+     * 'ADD' function. Adds two or more numbers.
+     *
+     * @param Expression|int|float ...$arguments
+     */
+    public static function add(Expression|int|float ...$arguments): self
+    {
+        if (count($arguments) < 2) {
+            throw new RuntimeException("Too few arguments.");
+        }
+
+        return self::composeFunction('ADD', ...$arguments);
+    }
+
+    /**
+     * 'SUB' function. Subtraction.
+     *
+     * @param Expression|int|float ...$arguments
+     */
+    public static function subtract(Expression|int|float ...$arguments): self
+    {
+        if (count($arguments) < 2) {
+            throw new RuntimeException("Too few arguments.");
+        }
+
+        return self::composeFunction('SUB', ...$arguments);
+    }
+
+    /**
+     * 'MUL' function. Multiplication.
+     *
+     * @param Expression|int|float ...$arguments
+     */
+    public static function multiply(Expression|int|float ...$arguments): self
+    {
+        if (count($arguments) < 2) {
+            throw new RuntimeException("Too few arguments.");
+        }
+
+        return self::composeFunction('MUL', ...$arguments);
+    }
+
+    /**
+     * 'DIV' function. Division.
+     *
+     * @param Expression|int|float ...$arguments
+     */
+    public static function divide(Expression|int|float ...$arguments): self
+    {
+        if (count($arguments) < 2) {
+            throw new RuntimeException("Too few arguments.");
+        }
+
+        return self::composeFunction('DIV', ...$arguments);
+    }
+
+    /**
+     * 'MOD' function. Returns a remainder of a number divided by another number.
+     *
+     * @param Expression|int|float ...$arguments
+     */
+    public static function modulo(Expression|int|float ...$arguments): self
+    {
+        if (count($arguments) < 2) {
+            throw new RuntimeException("Too few arguments.");
+        }
+
+        return self::composeFunction('MOD', ...$arguments);
+    }
+
+    /**
+     * 'FLOOR' function. The largest integer value not greater than the argument.
+     */
+    public static function floor(Expression $number): self
+    {
+        return self::composeFunction('FLOOR', $number);
+    }
+
+    /**
+     * 'CEIL' function. The largest integer value not greater than the argument.
+     */
+    public static function ceil(Expression $number): self
+    {
+        return self::composeFunction('CEIL', $number);
+    }
+
+    /**
+     * 'ROUND' function. Rounds a number to a specified number of decimal places.
+     */
+    public static function round(Expression $number, int $precision = 0): self
+    {
+        return self::composeFunction('ROUND', $number, $precision);
+    }
+
+    /**
+     * 'GREATEST' function. A max value from a list of expressions.
+     */
+    public static function greatest(Expression ...$arguments): self
+    {
+        return self::composeFunction('GREATEST', ...$arguments);
+    }
+
+    /**
+     * 'LEAST' function. A min value from a list of expressions.
+     */
+    public static function least(Expression ...$arguments): self
+    {
+        return self::composeFunction('LEAST', ...$arguments);
+    }
+
+    /**
+     * 'ANY_VALUE' function.
+     *
+     * @since 9.1.6
+     */
+    public function anyValue(Expression $expression): self
+    {
+        return self::composeFunction('ANY_VALUE', $expression);
+    }
+
+    /**
+     * 'AND' operator. Returns TRUE if all arguments are TRUE.
+     */
+    public static function and(Expression ...$arguments): self
+    {
+        return self::composeFunction('AND', ...$arguments);
+    }
+
+    /**
+     * 'OR' operator. Returns TRUE if at least one argument is TRUE.
+     */
+    public static function or(Expression ...$arguments): self
+    {
+        return self::composeFunction('OR', ...$arguments);
+    }
+
+    /**
+     * 'NOT' operator. Negates an expression.
+     */
+    public static function not(Expression $argument): self
+    {
+        return self::composeFunction('NOT', $argument);
+    }
+
+    /**
+     * 'ROW' constructor.
+     */
+    public static function row(Expression ...$arguments): self
+    {
+        return self::composeFunction('ROW', ...$arguments);
+    }
+
+    private static function composeFunction(
+        string $function,
+        Expression|bool|int|float|string|null ...$arguments
+    ): self {
+
+        return Util::composeFunction($function, ...$arguments);
+    }
+
+    private static function stringifyArgument(Expression|bool|int|float|string|null $argument): string
+    {
+        return Util::stringifyArgument($argument);
+    }
+}

application/Espo/ORM/Query/Part/Expression/Util.php

@@ -0,0 +1,88 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part\Expression;
+
+use Espo\ORM\Query\Part\Expression;
+
+class Util
+{
+    /**
+     * Compose an expression by a function name and arguments.
+     *
+     * @param Expression|bool|int|float|string|null ...$arguments Arguments
+     */
+    public static function composeFunction(
+        string $function,
+        Expression|bool|int|float|string|null ...$arguments
+    ): Expression {
+
+        $stringifiedItems = array_map(
+            function ($item) {
+                return self::stringifyArgument($item);
+            },
+            $arguments
+        );
+
+        $expression = $function . ':(' . implode(', ', $stringifiedItems) . ')';
+
+        return Expression::create($expression);
+    }
+
+    /**
+     * Stringify an argument.
+     *
+     * @param Expression|bool|int|float|string|null $argument
+     */
+    public static function stringifyArgument(Expression|bool|int|float|string|null $argument): string
+    {
+
+        if ($argument instanceof Expression) {
+            return $argument->getValue();
+        }
+
+        if (is_null($argument)) {
+            return 'NULL';
+        }
+
+       if (is_bool($argument)) {
+            return $argument ? 'TRUE': 'FALSE';
+        }
+
+       if (is_int($argument)) {
+           return strval($argument);
+       }
+
+       if (is_float($argument)) {
+           return strval($argument);
+       }
+
+       return '\'' . str_replace('\'', '\\\'', $argument) . '\'';
+    }
+}

application/Espo/ORM/Query/Part/Join.php

@@ -0,0 +1,300 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part;
+
+use Espo\ORM\Query\Part\Join\JoinType;
+use Espo\ORM\Query\Select;
+use LogicException;
+use RuntimeException;
+
+/**
+ * A join item. Immutable.
+ */
+class Join
+{
+    /** A table join. */
+    public const MODE_TABLE = 0;
+    /** A relation join. */
+    public const MODE_RELATION = 1;
+    /** A sub-query join. */
+    public const MODE_SUB_QUERY = 3;
+
+    private ?WhereItem $conditions = null;
+    private bool $onlyMiddle = false;
+    private bool $isLateral = false;
+    private ?JoinType $type = null;
+
+    private function __construct(
+        private string|Select $target,
+        private ?string $alias = null
+    ) {
+        if ($target === '' || $alias === '') {
+            throw new RuntimeException("Bad join.");
+        }
+    }
+
+    /**
+     * Get a join target. A relation name, table or sub-query.
+     * A relation name is in camelCase, a table is in CamelCase.
+     */
+    public function getTarget(): string|Select
+    {
+        return $this->target;
+    }
+
+    /**
+     * Get an alias.
+     */
+    public function getAlias(): ?string
+    {
+        return $this->alias;
+    }
+
+    /**
+     * Get join conditions.
+     */
+    public function getConditions(): ?WhereItem
+    {
+        return $this->conditions;
+    }
+
+    /**
+     * Is a sub-query join.
+     */
+    public function isSubQuery(): bool
+    {
+        return !is_string($this->target);
+    }
+
+    /**
+     * Is a table join.
+     */
+    public function isTable(): bool
+    {
+        return is_string($this->target) && $this->target[0] === ucfirst($this->target[0]);
+    }
+
+    /**
+     * Is a relation join.
+     */
+    public function isRelation(): bool
+    {
+        return !$this->isSubQuery() && !$this->isTable();
+    }
+
+    /**
+     * Get a join mode.
+     *
+     * @return self::MODE_TABLE|self::MODE_RELATION|self::MODE_SUB_QUERY
+     */
+    public function getMode(): int
+    {
+        if ($this->isSubQuery()) {
+            return self::MODE_SUB_QUERY;
+        }
+
+        if ($this->isRelation()) {
+            return self::MODE_RELATION;
+        }
+
+        return self::MODE_TABLE;
+    }
+
+    /**
+     * Is only middle table to be joined.
+     */
+    public function isOnlyMiddle(): bool
+    {
+        return $this->onlyMiddle;
+    }
+
+    /**
+     * Is LATERAL.
+     *
+     * @since 9.1.6
+     */
+    public function isLateral(): bool
+    {
+        return $this->isLateral;
+    }
+
+    /**
+     * Get a join type.
+     *
+     * @return JoinType|null
+     *
+     * @since 9.2.0
+     */
+    public function getType(): ?JoinType
+    {
+        return $this->type;
+    }
+
+    /**
+     * Create.
+     *
+     * @param string|Select $target
+     * A relation name, table or sub-query. A relation name should be in camelCase, a table in CamelCase.
+     * When joining a table or sub-query, conditions should be specified.
+     * When joining a relation, conditions will be applied automatically, additional conditions can
+     * be specified as well.
+     * @param ?string $alias An alias.
+     */
+    public static function create(string|Select $target, ?string $alias = null): self
+    {
+        return new self($target, $alias);
+    }
+
+    /**
+     * Create with a table target.
+     *
+     * @param string $table A table name. Should start with an upper case letter.
+     * @param ?string $alias An alias.
+     */
+    public static function createWithTableTarget(string $table, ?string $alias = null): self
+    {
+        return self::create(ucfirst($table), $alias);
+    }
+
+    /**
+     * Create with a relation target. Conditions will be applied automatically.
+     *
+     * @param string $relation A relation name. Should start with a lower case letter.
+     * @param ?string $alias An alias.
+     */
+    public static function createWithRelationTarget(string $relation, ?string $alias = null): self
+    {
+        return self::create(lcfirst($relation), $alias);
+    }
+
+    /**
+     * Create with a sub-query.
+     *
+     * @param Select $subQuery A sub-query.
+     * @param string $alias An alias.
+     */
+    public static function createWithSubQuery(Select $subQuery, string $alias): self
+    {
+        return new self($subQuery, $alias);
+    }
+
+    /**
+     * Clone with an alias.
+     */
+    public function withAlias(?string $alias): self
+    {
+        $obj = clone $this;
+        $obj->alias = $alias;
+
+        return $obj;
+    }
+
+    /**
+     * Clone with join conditions.
+     */
+    public function withConditions(?WhereItem $conditions): self
+    {
+        $obj = clone $this;
+        $obj->conditions = $conditions;
+
+        return $obj;
+    }
+
+    /**
+     * Join only middle table. For many-to-many relationships.
+     */
+    public function withOnlyMiddle(bool $onlyMiddle = true): self
+    {
+        if (!$this->isRelation()) {
+            throw new LogicException("Only-middle is compatible only with relation joins.");
+        }
+
+        $obj = clone $this;
+        $obj->onlyMiddle = $onlyMiddle;
+
+        return $obj;
+    }
+
+    /**
+     * With LATERAL. Only for a sub-query join.
+     *
+     * @since 9.1.6
+     */
+    public function withLateral(bool $isLateral = true): self
+    {
+        if (!$this->isSubQuery()) {
+            throw new LogicException("Lateral can be used only with sub-query joins.");
+        }
+
+        $obj = clone $this;
+        $obj->isLateral = $isLateral;
+
+        return $obj;
+    }
+
+    /**
+     * With LEFT type.
+     *
+     * @since 9.2.0.
+     */
+    public function withLeft(): self
+    {
+        $obj = clone $this;
+        $obj->type = JoinType::left;
+
+        return $obj;
+    }
+
+    /**
+     * With INNER type.
+     *
+     * @since 9.2.0.
+     */
+    public function withInner(): self
+    {
+        $obj = clone $this;
+        $obj->type = JoinType::inner;
+
+        return $obj;
+    }
+
+    /**
+     * With a join type.
+     *
+     * @since 9.2.0.
+     */
+    public function withType(JoinType $type): self
+    {
+        $obj = clone $this;
+        $obj->type = $type;
+
+        return $obj;
+    }
+}

application/Espo/ORM/Query/Part/Join/JoinType.php

@@ -0,0 +1,46 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part\Join;
+
+/**
+ * @since 9.2.0
+ */
+enum JoinType: string
+{
+    /**
+     * An INNER join.
+     */
+    case inner = 'inner';
+
+    /**
+     * A LEFT join.
+     */
+    case left = 'left';
+}

application/Espo/ORM/Query/Part/Order.php

@@ -0,0 +1,156 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part;
+
+use RuntimeException;
+
+/**
+ * An order item. Immutable.
+ *
+ * Immutable.
+ */
+class Order
+{
+    public const ASC = 'ASC';
+    public const DESC = 'DESC';
+
+    private Expression $expression;
+    private bool $isDesc = false;
+
+    private function __construct(Expression $expression)
+    {
+        $this->expression = $expression;
+    }
+
+    /**
+     * Get an expression.
+     */
+    public function getExpression(): Expression
+    {
+        return $this->expression;
+    }
+
+    public function isDesc(): bool
+    {
+        return $this->isDesc;
+    }
+
+    /**
+     * Get a direction.
+     *
+     * @return self::DESC|self::ASC
+     */
+    public function getDirection(): string
+    {
+        return $this->isDesc ? self::DESC : self::ASC;
+    }
+
+    /**
+     * Create.
+     */
+    public static function create(Expression $expression): self
+    {
+        return new self($expression);
+    }
+
+    /**
+     * Create from a string expression.
+     */
+    public static function fromString(string $expression): self
+    {
+        return self::create(
+            Expression::create($expression)
+        );
+    }
+
+    /**
+     * Create an order by position in list.
+     * Note: Reverses the list and applies DESC order.
+     *
+     * @param string[]|int[]|float[] $list
+     */
+    public static function createByPositionInList(Expression $expression, array $list): self
+    {
+        $orderExpression = Expression::positionInList($expression, array_reverse($list));
+
+        return self::create($orderExpression)->withDesc();
+    }
+
+    /**
+     * Clone with an ascending direction.
+     */
+    public function withAsc(): self
+    {
+        $obj = clone $this;
+        $obj->isDesc = false;
+
+        return $obj;
+    }
+
+    /**
+     * Clone with a descending direction.
+     */
+    public function withDesc(): self
+    {
+        $obj = clone $this;
+        $obj->isDesc = true;
+
+        return $obj;
+    }
+
+    /**
+     * Clone with a direction.
+     *
+     * @params self::ASC|self::DESC $direction
+     * @throws RuntimeException
+     */
+    public function withDirection(string $direction): self
+    {
+        $obj = clone $this;
+        $obj->isDesc = strtoupper($direction) === self::DESC;
+
+        if (!in_array(strtoupper($direction), [self::DESC, self::ASC])) {
+            throw new RuntimeException("Bad order direction.");
+        }
+
+        return $obj;
+    }
+
+    /**
+     * Clone with a reverse direction.
+     */
+    public function withReverseDirection(): self
+    {
+        $obj = clone $this;
+        $obj->isDesc = !$this->isDesc;
+
+        return $obj;
+    }
+}

application/Espo/ORM/Query/Part/OrderList.php

@@ -0,0 +1,96 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part;
+
+use InvalidArgumentException;
+use Iterator;
+
+/**
+ * A list of order items.
+ *
+ * Immutable.
+ *
+ * @implements Iterator<Order>
+ */
+class OrderList implements Iterator
+{
+    private int $position = 0;
+    /** @var Order[] */
+    private array $list;
+
+    /**
+     * @param Order[] $list
+     */
+    private function __construct(array $list)
+    {
+        foreach ($list as $item) {
+            if (!$item instanceof Order) {
+                throw new InvalidArgumentException();
+            }
+        }
+
+        $this->list = $list;
+    }
+
+    /**
+     * Create an instance.
+     *
+     * @param Order[] $list
+     */
+    public static function create(array $list): self
+    {
+        return new self($list);
+    }
+
+    public function rewind(): void
+    {
+        $this->position = 0;
+    }
+
+    public function current(): Order
+    {
+        return $this->list[$this->position];
+    }
+
+    public function key(): int
+    {
+        return $this->position;
+    }
+
+    public function next(): void
+    {
+        ++$this->position;
+    }
+
+    public function valid(): bool
+    {
+        return isset($this->list[$this->position]);
+    }
+}

application/Espo/ORM/Query/Part/Selection.php

@@ -0,0 +1,73 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part;
+
+/**
+ * A select item. Immutable.
+ *
+ * Immutable.
+ */
+class Selection
+{
+    private function __construct(
+        private Expression $expression,
+        private ?string $alias = null
+    ) {}
+
+    public function getExpression(): Expression
+    {
+        return $this->expression;
+    }
+
+    public function getAlias(): ?string
+    {
+        return $this->alias;
+    }
+
+    public static function create(Expression $expression, ?string $alias = null): self
+    {
+        return new self($expression, $alias);
+    }
+
+    public static function fromString(string $expression): self
+    {
+        return self::create(
+            Expression::create($expression)
+        );
+    }
+
+    public function withAlias(?string $alias): self
+    {
+        $obj = clone $this;
+        $obj->alias = $alias;
+
+        return $obj;
+    }
+}

application/Espo/ORM/Query/Part/Where/AndGroup.php

@@ -0,0 +1,108 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part\Where;
+
+use Espo\ORM\Query\Part\WhereClause;
+use Espo\ORM\Query\Part\WhereItem;
+
+/**
+ * AND-group. Immutable.
+ */
+class AndGroup implements WhereItem
+{
+    /** @var array<string|int, mixed> */
+    private $rawValue = [];
+
+    /**
+     * @return array<string|int, mixed>
+     */
+    public function getRaw(): array
+    {
+        return ['AND' => $this->getRawValue()];
+    }
+
+    public function getRawKey(): string
+    {
+        return 'AND';
+    }
+
+    /**
+     * @return array<string|int, mixed>
+     */
+    public function getRawValue(): array
+    {
+        return $this->rawValue;
+    }
+
+    /**
+     * Get a number of items.
+     */
+    public function getItemCount(): int
+    {
+        return count($this->rawValue);
+    }
+
+    /**
+     * @param array<string|int, mixed> $whereClause
+     * @return self
+     */
+    public static function fromRaw(array $whereClause): self
+    {
+        if (count($whereClause) === 1 && array_keys($whereClause)[0] === 0) {
+            $whereClause = $whereClause[0];
+        }
+
+        // Do not refactor.
+        $obj = static::class === WhereClause::class ?
+            new WhereClause() :
+            new self();
+
+        /** @phpstan-ignore-next-line */
+        $obj->rawValue = $whereClause;
+
+        return $obj;
+    }
+
+    public static function create(WhereItem ...$itemList): self
+    {
+        $builder = self::createBuilder();
+
+        foreach ($itemList as $item) {
+            $builder->add($item);
+        }
+
+        return $builder->build();
+    }
+
+    public static function createBuilder(): AndGroupBuilder
+    {
+        return new AndGroupBuilder();
+    }
+}

application/Espo/ORM/Query/Part/Where/AndGroupBuilder.php

@@ -0,0 +1,95 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part\Where;
+
+use Espo\ORM\Query\Part\WhereItem;
+
+class AndGroupBuilder
+{
+    /** @var array<string|int, mixed> */
+    private array $raw = [];
+
+    public function build(): AndGroup
+    {
+        return AndGroup::fromRaw($this->raw);
+    }
+
+    public function add(WhereItem $item): self
+    {
+        $key = $item->getRawKey();
+        $value = $item->getRawValue();
+
+        if ($item instanceof AndGroup) {
+            $this->raw = self::normalizeRaw($this->raw);
+
+            $this->raw[] = $item->getRawValue();
+
+            return $this;
+        }
+
+        if (count($this->raw) === 0) {
+            $this->raw[$key] = $value;
+
+            return $this;
+        }
+
+        $this->raw = self::normalizeRaw($this->raw);
+
+        $this->raw[] = [$key => $value];
+
+        return $this;
+    }
+
+    /**
+     * Merge with another AndGroup.
+     */
+    public function merge(AndGroup $andGroup): self
+    {
+        $this->raw = array_merge(
+            self::normalizeRaw($this->raw),
+            self::normalizeRaw($andGroup->getRawValue())
+        );
+
+        return $this;
+    }
+
+    /**
+     * @param array<string|int, mixed> $raw
+     * @return array<string|int, mixed>
+     */
+    private static function normalizeRaw(array $raw): array
+    {
+        if (count($raw) === 1 && array_keys($raw)[0] !== 0) {
+            return [$raw];
+        }
+
+        return $raw;
+    }
+}

application/Espo/ORM/Query/Part/Where/Comparison.php

@@ -0,0 +1,433 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part\Where;
+
+use Espo\ORM\Query\Part\Expression;
+use Espo\ORM\Query\Part\WhereItem;
+use Espo\ORM\Query\Select;
+
+use RuntimeException;
+
+/**
+ * Compares an expression to a value or another expression. Immutable.
+ */
+class Comparison implements WhereItem
+{
+    private const OPERATOR_EQUAL = '=';
+    private const OPERATOR_NOT_EQUAL = '!=';
+    private const OPERATOR_GREATER = '>';
+    private const OPERATOR_GREATER_OR_EQUAL = '>=';
+    private const OPERATOR_LESS = '<';
+    private const OPERATOR_LESS_OR_EQUAL = '<=';
+    private const OPERATOR_LIKE = '*';
+    private const OPERATOR_NOT_LIKE = '!*';
+    private const OPERATOR_IN_SUB_QUERY = '=s';
+    private const OPERATOR_NOT_IN_SUB_QUERY = '!=s';
+    private const OPERATOR_NOT_EQUAL_ANY = '!=any';
+    private const OPERATOR_GREATER_ANY = '>any';
+    private const OPERATOR_GREATER_OR_EQUAL_ANY = '>=any';
+    private const OPERATOR_LESS_ANY = '<any';
+    private const OPERATOR_LESS_OR_EQUAL_ANY = '<=any';
+    private const OPERATOR_EQUAL_ALL = '=all';
+    private const OPERATOR_GREATER_ALL = '>all';
+    private const OPERATOR_GREATER_OR_EQUAL_ALL = '>=all';
+    private const OPERATOR_LESS_ALL = '<all';
+    private const OPERATOR_LESS_OR_EQUAL_ALL = '<=all';
+
+    private string $rawKey;
+    private mixed $rawValue;
+
+    private function __construct(string $rawKey, mixed $rawValue)
+    {
+        $this->rawKey = $rawKey;
+        $this->rawValue = $rawValue;
+    }
+
+    public function getRaw(): array
+    {
+        return [$this->rawKey => $this->rawValue];
+    }
+
+    public function getRawKey(): string
+    {
+        return $this->rawKey;
+    }
+
+    public function getRawValue(): mixed
+    {
+        return $this->rawValue;
+    }
+
+    /**
+     * Create '=' comparison.
+     *
+     * @param Expression $argument1 An expression.
+     * @param Expression|Select|string|int|float|bool|null $argument2 A scalar, expression or sub-query.
+     * @return self
+     */
+    public static function equal(
+        Expression $argument1,
+        Expression|Select|string|int|float|bool|null $argument2
+    ): self {
+
+        return self::createComparison(self::OPERATOR_EQUAL, $argument1, $argument2);
+    }
+
+    /**
+     * Create '!=' comparison.
+     *
+     * @param Expression $argument1 An expression.
+     * @param Expression|Select|string|int|float|bool|null $argument2 A scalar, expression or sub-query.
+     * @return self
+     */
+    public static function notEqual(
+        Expression $argument1,
+        Expression|Select|string|int|float|bool|null $argument2
+    ): self {
+
+        return self::createComparison(self::OPERATOR_NOT_EQUAL, $argument1, $argument2);
+    }
+
+    /**
+     * Create 'LIKE' comparison.
+     *
+     * @param Expression $subject What to test.
+     * @param Expression|string $pattern A pattern.
+     * @return self
+     */
+    public static function like(Expression $subject, Expression|string $pattern): self
+    {
+        return self::createComparison(self::OPERATOR_LIKE, $subject, $pattern);
+    }
+
+    /**
+     * Create 'NOT LIKE' comparison.
+     *
+     * @param Expression $subject What to test.
+     * @param Expression|string $pattern A pattern.
+     * @return self
+     */
+    public static function notLike(Expression $subject, Expression|string $pattern): self
+    {
+        return self::createComparison(self::OPERATOR_NOT_LIKE, $subject, $pattern);
+    }
+
+    /**
+     * Create '>' comparison.
+     *
+     * @param Expression $argument1 An expression.
+     * @param Expression|Select|string|int|float $argument2 A scalar, expression or sub-query.
+     * @return self
+     */
+    public static function greater(Expression $argument1, Expression|Select|string|int|float $argument2): self
+    {
+        return self::createComparison(self::OPERATOR_GREATER, $argument1, $argument2);
+    }
+
+    /**
+     * Create '>=' comparison.
+     *
+     * @param Expression $argument1 An expression.
+     * @param Expression|Select|string|int|float $argument2 A scalar, expression or sub-query.
+     * @return self
+     */
+    public static function greaterOrEqual(Expression $argument1, Expression|Select|string|int|float $argument2): self
+    {
+        return self::createComparison(self::OPERATOR_GREATER_OR_EQUAL, $argument1, $argument2);
+    }
+
+    /**
+     * Create '<' comparison.
+     *
+     * @param Expression $argument1 An expression.
+     * @param Expression|Select|string|int|float $argument2 A scalar, expression or sub-query.
+     * @return self
+     */
+    public static function less(Expression $argument1, Expression|Select|string|int|float $argument2): self
+    {
+        return self::createComparison(self::OPERATOR_LESS, $argument1, $argument2);
+    }
+
+    /**
+     * Create '<=' comparison.
+     *
+     * @param Expression $argument1 An expression.
+     * @param Expression|Select|string|int|float $argument2 A scalar, expression or sub-query.
+     * @return self
+     */
+    public static function lessOrEqual(Expression $argument1, Expression|Select|string|int|float $argument2): self
+    {
+        return self::createComparison(self::OPERATOR_LESS_OR_EQUAL, $argument1, $argument2);
+    }
+
+    /**
+     * Create 'IN' comparison.
+     *
+     * @param Expression $subject What to test.
+     * @param Select|scalar[] $set A set of values. A select query or array of scalars.
+     * @return self
+     */
+    public static function in(Expression $subject, Select|array $set): self
+    {
+        if ($set instanceof Select) {
+            return self::createInOrNotInSubQuery(self::OPERATOR_IN_SUB_QUERY, $subject, $set);
+        }
+
+        return self::createInOrNotInArray(self::OPERATOR_EQUAL, $subject, $set);
+    }
+
+    /**
+     * Create 'NOT IN' comparison.
+     *
+     * @param Expression $subject What to test.
+     * @param Select|scalar[] $set A set of values. A select query or array of scalars.
+     * @return self
+     */
+    public static function notIn(Expression $subject, Select|array $set): self
+    {
+        if ($set instanceof Select) {
+            return self::createInOrNotInSubQuery(self::OPERATOR_NOT_IN_SUB_QUERY, $subject, $set);
+        }
+
+        return self::createInOrNotInArray(self::OPERATOR_NOT_EQUAL, $subject, $set);
+    }
+
+    /**
+     * Create '!= ANY' comparison.
+     *
+     * @param Expression $argument An expression.
+     * @param Select $subQuery A sub-query.
+     * @return self
+     */
+    public static function notEqualAny(Expression $argument, Select $subQuery): self
+    {
+        return self::createComparison(self::OPERATOR_NOT_EQUAL_ANY, $argument, $subQuery);
+    }
+
+    /**
+     * Create '> ANY' comparison.
+     *
+     * @param Expression $argument An expression.
+     * @param Select $subQuery A sub-query.
+     * @return self
+     */
+    public static function greaterAny(Expression $argument, Select $subQuery): self
+    {
+        return self::createComparison(self::OPERATOR_GREATER_ANY, $argument, $subQuery);
+    }
+
+    /**
+     * Create '< ANY' comparison.
+     *
+     * @param Expression $argument An expression.
+     * @param Select $subQuery A sub-query.
+     * @return self
+     */
+    public static function lessAny(Expression $argument, Select $subQuery): self
+    {
+        return self::createComparison(self::OPERATOR_LESS_ANY, $argument, $subQuery);
+    }
+
+    /**
+     * Create '>= ANY' comparison.
+     *
+     * @param Expression $argument An expression.
+     * @param Select $subQuery A sub-query.
+     * @return self
+     */
+    public static function greaterOrEqualAny(Expression $argument, Select $subQuery): self
+    {
+        return self::createComparison(self::OPERATOR_GREATER_OR_EQUAL_ANY, $argument, $subQuery);
+    }
+
+    /**
+     * Create '<= ANY' comparison.
+     *
+     * @param Expression $argument An expression.
+     * @param Select $subQuery A sub-query.
+     * @return self
+     */
+    public static function lessOrEqualAny(Expression $argument, Select $subQuery): self
+    {
+        return self::createComparison(self::OPERATOR_LESS_OR_EQUAL_ANY, $argument, $subQuery);
+    }
+
+    /**
+     * Create '= ALL' comparison.
+     *
+     * @param Expression $argument An expression.
+     * @param Select $subQuery A sub-query.
+     * @return self
+     */
+    public static function equalAll(Expression $argument, Select $subQuery): self
+    {
+        return self::createComparison(self::OPERATOR_EQUAL_ALL, $argument, $subQuery);
+    }
+
+    /**
+     * Create '> ALL' comparison.
+     *
+     * @param Expression $argument An expression.
+     * @param Select $subQuery A sub-query.
+     * @return self
+     */
+    public static function greaterAll(Expression $argument, Select $subQuery): self
+    {
+        return self::createComparison(self::OPERATOR_GREATER_ALL, $argument, $subQuery);
+    }
+
+    /**
+     * Create '< ALL' comparison.
+     *
+     * @param Expression $argument An expression.
+     * @param Select $subQuery A sub-query.
+     * @return self
+     */
+    public static function lessAll(Expression $argument, Select $subQuery): self
+    {
+        return self::createComparison(self::OPERATOR_LESS_ALL, $argument, $subQuery);
+    }
+
+    /**
+     * Create '>= ALL' comparison.
+     *
+     * @param Expression $argument An expression.
+     * @param Select $subQuery A sub-query.
+     * @return self
+     */
+    public static function greaterOrEqualAll(Expression $argument, Select $subQuery): self
+    {
+        return self::createComparison(self::OPERATOR_GREATER_OR_EQUAL_ALL, $argument, $subQuery);
+    }
+
+    /**
+     * Create '<= ALL' comparison.
+     *
+     * @param Expression $argument An expression.
+     * @param Select $subQuery A sub-query.
+     * @return self
+     */
+    public static function lessOrEqualAll(Expression $argument, Select $subQuery): self
+    {
+        return self::createComparison(self::OPERATOR_LESS_OR_EQUAL_ALL, $argument, $subQuery);
+    }
+
+    private static function createComparison(
+        string $operator,
+        Expression|string $argument1,
+        Expression|Select|string|int|float|bool|null $argument2
+    ): self {
+
+        if (is_string($argument1)) {
+            $key = $argument1;
+
+            if ($key === '') {
+                throw new RuntimeException("Expression can't be empty.");
+            }
+        } else {
+            $key = $argument1->getValue();
+        }
+
+        if (str_ends_with($key, ':')) {
+            throw new RuntimeException("Expression should not end with `:`.");
+        }
+
+        $key .= $operator;
+
+        if ($argument2 instanceof Expression) {
+            $key .= ':';
+
+            $value = $argument2->getValue();
+        } else {
+            $value = $argument2;
+        }
+
+        return new self($key, $value);
+    }
+
+    /**
+     * @param scalar[] $valueList
+     */
+    private static function createInOrNotInArray(
+        string $operator,
+        Expression|string $argument1,
+        array $valueList
+    ): self {
+
+        foreach ($valueList as $item) {
+            if (!is_scalar($item)) {
+                throw new RuntimeException("Array items must be scalar.");
+            }
+        }
+
+        if (is_string($argument1)) {
+            $key = $argument1;
+
+            if ($key === '') {
+                throw new RuntimeException("Expression can't be empty.");
+            }
+
+            if (str_ends_with($key, ':')) {
+                throw new RuntimeException("Expression can't end with `:`.");
+            }
+        } else {
+            $key = $argument1->getValue();
+        }
+
+        $key .= $operator;
+
+        return new self($key, $valueList);
+    }
+
+    private static function createInOrNotInSubQuery(
+        string $operator,
+        Expression|string $argument1,
+        Select $query
+    ): self {
+
+        if (is_string($argument1)) {
+            $key = $argument1;
+
+            if ($key === '') {
+                throw new RuntimeException("Expression can't be empty.");
+            }
+
+            if (str_ends_with($key, ':')) {
+                throw new RuntimeException("Expression can't end with `:`.");
+            }
+        } else {
+            $key = $argument1->getValue();
+        }
+
+        $key .= $operator;
+
+        return new self($key, $query);
+    }
+}

application/Espo/ORM/Query/Part/Where/Exists.php

@@ -0,0 +1,61 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part\Where;
+
+use Espo\ORM\Query\Part\WhereItem;
+use Espo\ORM\Query\Select;
+
+/**
+ * An EXISTS-operator. Immutable.
+ */
+class Exists implements WhereItem
+{
+    private function __construct(private Select $rawValue) {}
+
+    public function getRaw(): array
+    {
+        return ['EXISTS' => $this->getRawValue()];
+    }
+
+    public function getRawKey(): string
+    {
+        return 'EXISTS';
+    }
+
+    public function getRawValue(): Select
+    {
+        return $this->rawValue;
+    }
+
+    public static function create(Select $subQuery): self
+    {
+        return new self($subQuery);
+    }
+}

application/Espo/ORM/Query/Part/Where/Not.php

@@ -0,0 +1,80 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part\Where;
+
+use Espo\ORM\Query\Part\WhereItem;
+
+/**
+ * A NOT-operator. Immutable.
+ */
+class Not implements WhereItem
+{
+    /** @var array<string|int, mixed> */
+    private $rawValue = [];
+
+    public function getRaw(): array
+    {
+        return ['NOT' => $this->getRawValue()];
+    }
+
+    public function getRawKey(): string
+    {
+        return 'NOT';
+    }
+
+    /**
+     * @return array<string|int, mixed>
+     */
+    public function getRawValue(): array
+    {
+        return $this->rawValue;
+    }
+
+    /**
+     * @param array<string|int, mixed> $whereClause
+     */
+    public static function fromRaw(array $whereClause): self
+    {
+        if (count($whereClause) === 1 && array_keys($whereClause)[0] === 0) {
+            $whereClause = $whereClause[0];
+        }
+
+        $obj = new self();
+
+        $obj->rawValue = $whereClause;
+
+        return $obj;
+    }
+
+    public static function create(WhereItem $item): self
+    {
+        return self::fromRaw($item->getRaw());
+    }
+}

application/Espo/ORM/Query/Part/Where/OrGroup.php

@@ -0,0 +1,100 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part\Where;
+
+use Espo\ORM\Query\Part\WhereItem;
+
+/**
+ * OR-group. Immutable.
+ */
+class OrGroup implements WhereItem
+{
+
+    /** @var array<string|int, mixed> */
+    private $rawValue = [];
+
+    public function __construct()
+    {
+    }
+
+    public function getRaw(): array
+    {
+        return ['OR' => $this->rawValue];
+    }
+
+    public function getRawKey(): string
+    {
+        return 'OR';
+    }
+
+    /**
+     * @return array<string|int, mixed>
+     */
+    public function getRawValue(): array
+    {
+        return $this->rawValue;
+    }
+
+    /**
+     * Get a number of items.
+     */
+    public function getItemCount(): int
+    {
+        return count($this->rawValue);
+    }
+
+    /**
+     * @param array<string|int, mixed> $whereClause
+     */
+    public static function fromRaw(array $whereClause): self
+    {
+        $obj = new self();
+
+        $obj->rawValue = $whereClause;
+
+        return $obj;
+    }
+
+    public static function create(WhereItem ...$itemList): self
+    {
+        $builder = self::createBuilder();
+
+        foreach ($itemList as $item) {
+            $builder->add($item);
+        }
+
+        return $builder->build();
+    }
+
+    public static function createBuilder(): OrGroupBuilder
+    {
+        return new OrGroupBuilder();
+    }
+}

application/Espo/ORM/Query/Part/Where/OrGroupBuilder.php

@@ -0,0 +1,95 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part\Where;
+
+use Espo\ORM\Query\Part\WhereItem;
+
+class OrGroupBuilder
+{
+    /** @var array<string|int, mixed> */
+    private array $raw = [];
+
+    public function build(): OrGroup
+    {
+        return OrGroup::fromRaw($this->raw);
+    }
+
+    public function add(WhereItem $item): self
+    {
+        $key = $item->getRawKey();
+        $value = $item->getRawValue();
+
+        if ($item instanceof AndGroup) {
+            $this->raw = self::normalizeRaw($this->raw);
+
+            $this->raw[] = $value;
+
+            return $this;
+        }
+
+        if (count($this->raw) === 0) {
+            $this->raw[$key] = $value;
+
+            return $this;
+        }
+
+        $this->raw = self::normalizeRaw($this->raw);
+
+        $this->raw[] = [$key => $value];
+
+        return $this;
+    }
+
+    /**
+     * Merge with another OrGroup.
+     */
+    public function merge(OrGroup $orGroup): self
+    {
+        $this->raw = array_merge(
+            self::normalizeRaw($this->raw),
+            self::normalizeRaw($orGroup->getRawValue())
+        );
+
+        return $this;
+    }
+
+    /**
+     * @param array<string|int, mixed> $raw
+     * @return array<string|int, mixed>
+     */
+    private static function normalizeRaw(array $raw): array
+    {
+        if (count($raw) === 1 && array_keys($raw)[0] !== 0) {
+            return [$raw];
+        }
+
+        return $raw;
+    }
+}

application/Espo/ORM/Query/Part/WhereClause.php

@@ -0,0 +1,45 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part;
+
+use Espo\ORM\Query\Part\Where\AndGroup;
+
+/**
+ * A where-clause. Immutable.
+ *
+ * Immutable.
+ */
+class WhereClause extends AndGroup
+{
+    public function getRaw(): array
+    {
+        return $this->getRawValue();
+    }
+}

application/Espo/ORM/Query/Part/WhereItem.php

@@ -0,0 +1,45 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query\Part;
+
+/**
+ * Can be used as a where-clause.
+ */
+interface WhereItem
+{
+    /**
+     * @return array<string|int, mixed>
+     */
+    public function getRaw(): array;
+
+    public function getRawKey(): string;
+
+    public function getRawValue(): mixed;
+}

application/Espo/ORM/Query/Query.php

@@ -0,0 +1,43 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+/**
+ * Query parameters. Instances are immutable. Need to clone with a builder to get a copy for a further modification.
+ */
+interface Query
+{
+    /**
+     * Get parameters in RAW format.
+     *
+     * @return array<string, mixed>
+     */
+    public function getRaw(): array;
+}

application/Espo/ORM/Query/Select.php

@@ -0,0 +1,207 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use Espo\ORM\Query\Part\WhereClause;
+use Espo\ORM\Query\Part\Selection;
+use Espo\ORM\Query\Part\Order;
+use Espo\ORM\Query\Part\Expression;
+
+use RuntimeException;
+
+/**
+ * Select parameters.
+ *
+ * Immutable.
+ *
+ * @todo Add validation and normalization.
+ */
+class Select implements SelectingQuery
+{
+    use SelectingTrait;
+    use BaseTrait;
+
+    public const ORDER_ASC = Order::ASC;
+    public const ORDER_DESC = Order::DESC;
+
+    /**
+     * Get an entity type.
+     */
+    public function getFrom(): ?string
+    {
+        return $this->params['from'] ?? null;
+    }
+
+    /**
+     * Get a from-alias
+     */
+    public function getFromAlias(): ?string
+    {
+        return $this->params['fromAlias'] ?? null;
+    }
+
+    /**
+     * Get a from-query.
+     */
+    public function getFromQuery(): ?SelectingQuery
+    {
+        return $this->params['fromQuery'] ?? null;
+    }
+
+    /**
+     * Get an OFFSET.
+     */
+    public function getOffset(): ?int
+    {
+        return $this->params['offset'] ?? null;
+    }
+
+    /**
+     * Get a LIMIT.
+     */
+    public function getLimit(): ?int
+    {
+        return $this->params['limit'] ?? null;
+    }
+
+    /**
+     * Get USE INDEX (list of indexes).
+     *
+     * @return string[]
+     */
+    public function getUseIndex(): array
+    {
+        return $this->params['useIndex'] ?? [];
+    }
+
+    /**
+     * Get SELECT items.
+     *
+     * @return Selection[]
+     */
+    public function getSelect(): array
+    {
+        return array_map(
+            function ($item) {
+                if (is_array($item) && count($item)) {
+                    return Selection::fromString($item[0])
+                        ->withAlias($item[1] ?? null);
+                }
+
+                if (is_string($item)) {
+                    return Selection::fromString($item);
+                }
+
+                throw new RuntimeException("Bad select item.");
+            },
+            $this->params['select'] ?? []
+        );
+    }
+
+    /**
+     * Whether DISTINCT is applied.
+     */
+    public function isDistinct(): bool
+    {
+        return $this->params['distinct'] ?? false;
+    }
+
+    /**
+     * Whether a FOR SHARE lock mode is set.
+     */
+    public function isForShare(): bool
+    {
+        return $this->params['forShare'] ?? false;
+    }
+
+    /**
+     * Whether a FOR UPDATE lock mode is set.
+     */
+    public function isForUpdate(): bool
+    {
+        return $this->params['forUpdate'] ?? false;
+    }
+
+    /**
+     * Get GROUP BY items.
+     *
+     * @return Expression[]
+     */
+    public function getGroup(): array
+    {
+        return array_map(
+            function (string $item) {
+                return Expression::create($item);
+            },
+            $this->params['groupBy'] ?? []
+        );
+    }
+
+    /**
+     * Get HAVING clause.
+     */
+    public function getHaving(): ?WhereClause
+    {
+        $havingClause = $this->params['havingClause'] ?? null;
+
+        if ($havingClause === null || $havingClause === []) {
+            return null;
+        }
+
+        $having = WhereClause::fromRaw($havingClause);
+
+        if (!$having instanceof WhereClause) {
+            throw new RuntimeException();
+        }
+
+        return $having;
+    }
+
+    /**
+     * @param array<string, mixed> $params
+     */
+    private function validateRawParams(array $params): void
+    {
+        $this->validateRawParamsSelecting($params);
+
+        if (
+            (
+                !empty($params['joins']) ||
+                !empty($params['leftJoins']) ||
+                !empty($params['whereClause']) ||
+                !empty($params['orderBy'])
+            )
+            &&
+            empty($params['from']) && empty($params['fromQuery'])
+        ) {
+            throw new RuntimeException("Select params: Missing 'from'.");
+        }
+    }
+}

application/Espo/ORM/Query/SelectBuilder.php

@@ -0,0 +1,335 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use Espo\ORM\Query\Part\Expression;
+use Espo\ORM\Query\Part\Selection;
+use Espo\ORM\Query\Part\WhereItem;
+
+use InvalidArgumentException;
+use RuntimeException;
+
+class SelectBuilder implements Builder
+{
+    use SelectingBuilderTrait;
+
+    /**
+     * Create an instance.
+     */
+    public static function create(): self
+    {
+        return new self();
+    }
+
+    /**
+     * Build a SELECT query.
+     */
+    public function build(): Select
+    {
+        return Select::fromRaw($this->params);
+    }
+
+    /**
+     * Clone an existing query for a subsequent modifying and building.
+     */
+    public function clone(Select $query): self
+    {
+        $this->cloneInternal($query);
+
+        return $this;
+    }
+
+    /**
+     * Set FROM. For what entity type to build a query.
+     */
+    public function from(string $entityType, ?string $alias = null): self
+    {
+        if (isset($this->params['from']) && $entityType !== $this->params['from']) {
+            throw new RuntimeException("Method 'from' can be called only once.");
+        }
+
+        if (isset($this->params['fromQuery'])) {
+            throw new RuntimeException("Method 'from' can't be if 'fromQuery' is set.");
+        }
+
+        $this->params['from'] = $entityType;
+
+        if ($alias) {
+            $this->params['fromAlias'] = $alias;
+        }
+
+        return $this;
+    }
+
+    /**
+     * Set FROM sub-query.
+     */
+    public function fromQuery(SelectingQuery $query, string $alias): self
+    {
+        if (isset($this->params['from'])) {
+            throw new RuntimeException("Method 'fromQuery' can be called only once.");
+        }
+
+        if (isset($this->params['fromQuery'])) {
+            throw new RuntimeException("Method 'fromQuery' can't be if 'from' is set.");
+        }
+
+        if ($alias === '') {
+            throw new RuntimeException("Alias can't be empty.");
+        }
+
+        $this->params['fromQuery'] = $query;
+        $this->params['fromAlias'] = $alias;
+
+        return $this;
+    }
+
+    /**
+     * Set DISTINCT parameter.
+     */
+    public function distinct(): self
+    {
+        $this->params['distinct'] = true;
+
+        return $this;
+    }
+
+    /**
+     * Apply OFFSET and LIMIT.
+     */
+    public function limit(?int $offset = null, ?int $limit = null): self
+    {
+        $this->params['offset'] = $offset;
+        $this->params['limit'] = $limit;
+
+        return $this;
+    }
+
+    /**
+     * Specify SELECT. Columns and expressions to be selected. If not called, then
+     * all entity attributes will be selected. Passing an array will reset
+     * previously set items. Passing a SelectExpression|Expression|string will append the item.
+     *
+     * Usage options:
+     * * `select(SelectExpression $expression)`
+     * * `select([$expr1, $expr2, ...])`
+     * * `select(string $expression, string $alias)`
+     *
+     * @param Selection|Selection[]|Expression|Expression[]|string[]|string|array<int, string[]|string> $select
+     * An array of expressions or one expression.
+     * @param string|null $alias An alias. Actual if the first parameter is not an array.
+     */
+    public function select($select, ?string $alias = null): self
+    {
+        /** @phpstan-var mixed $select */
+
+        if (is_array($select)) {
+            $this->params['select'] = $this->normalizeSelectExpressionArray($select);
+
+            return $this;
+        }
+
+        if ($select instanceof Expression) {
+            $select = $select->getValue();
+        } else if ($select instanceof Selection) {
+            $alias = $alias ?? $select->getAlias();
+            $select = $select->getExpression()->getValue();
+        }
+
+        if (is_string($select)) {
+            $this->params['select'] = $this->params['select'] ?? [];
+
+            $this->params['select'][] = $alias ?
+                [$select, $alias] :
+                $select;
+
+            return $this;
+        }
+
+        throw new InvalidArgumentException();
+    }
+
+    /**
+     * Specify GROUP BY.
+     * Passing an array will reset previously set items.
+     * Passing a string|Expression will append an item.
+     *
+     * Usage options:
+     * * `groupBy(Expression|string $expression)`
+     * * `groupBy([$expr1, $expr2, ...])`
+     *
+     * @param Expression|Expression[]|string|string[] $groupBy
+     */
+    public function group($groupBy): self
+    {
+        /** @phpstan-var mixed $groupBy */
+
+        if (is_array($groupBy)) {
+            $this->params['groupBy'] = $this->normalizeExpressionItemArray($groupBy);
+
+            return $this;
+        }
+
+        if ($groupBy instanceof Expression) {
+            $groupBy = $groupBy->getValue();
+        }
+
+        if (is_string($groupBy)) {
+            $this->params['groupBy'] = $this->params['groupBy'] ?? [];
+
+            $this->params['groupBy'][] = $groupBy;
+
+            return $this;
+        }
+
+        throw new InvalidArgumentException();
+    }
+
+    /**
+     * @deprecated Use `group` method.
+     * @param Expression|Expression[]|string|string[] $groupBy
+     */
+    public function groupBy($groupBy): self
+    {
+        return $this->group($groupBy);
+    }
+
+    /**
+     * Use index.
+     */
+    public function useIndex(string $index): self
+    {
+        $this->params['useIndex'] = $this->params['useIndex'] ?? [];
+
+        $this->params['useIndex'][] = $index;
+
+        return $this;
+    }
+
+    /**
+     * Add a HAVING clause.
+     *
+     * Usage options:
+     * * `having(WhereItem $clause)`
+     * * `having(array $clause)`
+     * * `having(string $key, string $value)`
+     *
+     * @param WhereItem|array<int|string, mixed>|string $clause A key or where clause.
+     * @param mixed[]|scalar|null $value A value. Omitted if the first argument is not string.
+     */
+    public function having($clause, $value = null): self
+    {
+        $this->applyWhereClause('havingClause', $clause, $value);
+
+        return $this;
+    }
+
+    /**
+     * Lock selected rows in shared mode. To be used within a transaction.
+     */
+    public function forShare(): self
+    {
+        if (isset($this->params['forUpdate'])) {
+            throw new RuntimeException("Can't use two lock modes together.");
+        }
+
+        $this->params['forShare'] = true;
+
+        return $this;
+    }
+
+    /**
+     * Lock selected rows. To be used within a transaction.
+     */
+    public function forUpdate(): self
+    {
+        if (isset($this->params['forShare'])) {
+            throw new RuntimeException("Can't use two lock modes together.");
+        }
+
+        $this->params['forUpdate'] = true;
+
+        return $this;
+    }
+
+    /**
+     * @todo Remove?
+     */
+    public function withDeleted(): self
+    {
+        $this->params['withDeleted'] = true;
+
+        return $this;
+    }
+
+    /**
+     * @param array<Expression|Selection|mixed[]> $itemList
+     * @return array<array{0: string, 1?: string}|string>
+     */
+    private function normalizeSelectExpressionArray(array $itemList): array
+    {
+        $resultList = [];
+
+        foreach ($itemList as $item) {
+            if ($item instanceof Expression) {
+                $resultList[] = $item->getValue();
+
+                continue;
+            }
+
+            if ($item instanceof Selection) {
+                $resultList[] = $item->getAlias() ?
+                    [$item->getExpression()->getValue(), $item->getAlias()] :
+                    [$item->getExpression()->getValue()];
+
+                continue;
+            }
+
+            if (!is_array($item) || !count($item) || !$item[0] instanceof Expression) {
+                /** @var array{0:string,1?:string} $item */
+                $resultList[] = $item;
+
+                continue;
+            }
+
+            $newItem = [$item[0]->getValue()];
+
+            if (count($item) > 1) {
+                $newItem[] = $item[1];
+            }
+
+            /** @var array{0: string, 1?: string} $newItem */
+
+            $resultList[] = $newItem;
+        }
+
+        return $resultList;
+    }
+}

application/Espo/ORM/Query/SelectingBuilderTrait.php

@@ -0,0 +1,429 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use Espo\ORM\Query\Part\WhereItem;
+use Espo\ORM\Query\Part\Expression;
+use Espo\ORM\Query\Part\Order;
+use Espo\ORM\Query\Part\Join;
+
+use InvalidArgumentException;
+use LogicException;
+use RuntimeException;
+
+trait SelectingBuilderTrait
+{
+    use BaseBuilderTrait;
+
+    /**
+     * Add a WHERE clause.
+     *
+     * Usage options:
+     * * `where(WhereItem $clause)`
+     * * `where(array $clause)`
+     * * `where(string $key, string $value)`
+     *
+     * @param WhereItem|array<string|int, mixed>|string $clause A key or where clause.
+     * @param mixed[]|scalar|null $value A value. Omitted if the first argument is not string.
+     */
+    public function where($clause, $value = null): self
+    {
+        $this->applyWhereClause('whereClause', $clause, $value);
+
+        return $this;
+    }
+
+    /**
+     * @param WhereItem|array<string|int, mixed>|string $clause A key or where clause.
+     * @param mixed[]|scalar|null $value A value. Omitted if the first argument is not string.
+     */
+    private function applyWhereClause(string $type, $clause, $value): void
+    {
+        if ($clause instanceof WhereItem) {
+            $clause = $clause->getRaw();
+        }
+
+        $this->params[$type] = $this->params[$type] ?? [];
+
+        $original = $this->params[$type];
+
+        if (!is_string($clause) && !is_array($clause)) {
+            throw new InvalidArgumentException("Bad where clause.");
+        }
+
+        if (is_array($clause)) {
+            $new = $clause;
+        }
+
+        if (is_string($clause)) {
+            $new = [$clause => $value];
+        }
+
+        $containsSameKeys = (bool) count(
+            array_intersect(
+                array_keys($new),
+                array_keys($original)
+            )
+        );
+
+        if ($containsSameKeys) {
+            $this->params[$type][] = $new;
+
+            return;
+        }
+
+        $this->params[$type] = $new + $original;
+    }
+
+    /**
+     * Apply ORDER. Passing an array will override previously set items.
+     * Passing non-array will append an item,
+     *
+     * Usage options:
+     * * `order(OrderExpression $expression)
+     * * `order([$expr1, $expr2, ...])
+     * * `order(string $expression, string $direction)
+     *
+     * @param Order|Order[]|Expression|string|array<int, string[]>|string[] $orderBy
+     * An attribute to order by or an array or order items.
+     * Passing an array will reset a previously set order.
+     * @param (Order::ASC|Order::DESC)|bool|null $direction A direction. True for DESC.
+     */
+    public function order($orderBy, $direction = null): self
+    {
+        if (is_bool($direction)) {
+            $direction = $direction ? Order::DESC : Order::ASC;
+        }
+
+        if (is_array($orderBy)) {
+            $this->params['orderBy'] = $this->normalizeOrderExpressionItemArray(
+                $orderBy,
+                $direction ?? Order::ASC
+            );
+
+            return $this;
+        }
+
+        if (!$orderBy) {
+            throw new InvalidArgumentException();
+        }
+
+        $this->params['orderBy'] = $this->params['orderBy'] ?? [];
+
+        if ($orderBy instanceof Expression) {
+            $orderBy = $orderBy->getValue();
+            $direction = $direction ?? Order::ASC;
+        } else if ($orderBy instanceof Order) {
+            $direction = $direction ?? $orderBy->getDirection();
+            $orderBy = $orderBy->getExpression()->getValue();
+        } else {
+            $direction = $direction ?? Order::ASC;
+        }
+
+        $this->params['orderBy'][] = [$orderBy, $direction];
+
+        return $this;
+    }
+
+    /**
+     * Add JOIN.
+     *
+     * @param Join|string|Select $target A relation name, table or sub-query. A relation name should be in camelCase,
+     *     a table in CamelCase.
+     * @param ?string $alias An alias.
+     * @param WhereItem|array<string|int, mixed>|null $conditions Join conditions.
+     */
+    public function join(
+        $target,
+        ?string $alias = null,
+        WhereItem|array|null $conditions = null
+    ): self {
+
+        return $this->joinInternal('joins', $target, $alias, $conditions);
+    }
+
+    /**
+     * Add LEFT JOIN.
+     *
+     * @param Join|string|Select $target A relation name, table or sub-query. A relation name should be in camelCase,
+     *     a table in CamelCase.
+     * @param ?string $alias An alias.
+     * @param WhereItem|array<string|int, mixed>|null $conditions Join conditions.
+     */
+    public function leftJoin(
+        $target,
+        ?string $alias = null,
+        WhereItem|array|null $conditions = null
+    ): self {
+
+        return $this->joinInternal('leftJoins', $target, $alias, $conditions);
+    }
+
+    /**
+     * @param 'leftJoins'|'joins' $type
+     * @todo Support USE INDEX in Join.
+     * @param Join|string|Select $target $target
+     * @param WhereItem|array<string|int, mixed>|null $conditions
+     */
+    private function joinInternal(
+        string $type,
+        $target,
+        ?string $alias = null,
+        WhereItem|array|null $conditions = null
+    ): self {
+
+        $onlyMiddle = false;
+        $isLateral = false;
+
+        /** @var string|Join|array<int, mixed> $target */
+
+        $joinType = null;
+
+        if ($target instanceof Join) {
+            $alias = $alias ?? $target->getAlias();
+            $conditions = $conditions ?? $target->getConditions();
+            $onlyMiddle = $target->isOnlyMiddle();
+            $isLateral = $target->isLateral();
+            $joinType = $target->getType();
+
+            $target = $target->getTarget();
+        }
+
+        if ($type === 'leftJoins') {
+            $joinType = Join\JoinType::left;
+        }
+
+        if ($target instanceof Select && !$alias) {
+            throw new LogicException("Sub-query join can't be used w/o alias.");
+        }
+
+        $noLeftAlias = false;
+
+        if ($conditions instanceof WhereItem) {
+            $conditions = $conditions->getRaw();
+
+            $noLeftAlias = true;
+        }
+
+        $this->params['joins'] ??= [];
+
+        // For bc.
+        // @todo Remove in v10.0.
+        if (is_array($target)) {
+            // @todo Log deprecation.
+
+            $joinList = $target;
+
+            $this->params[$type] ??= [];
+
+            foreach ($joinList as $item) {
+                $this->params[$type][] = $item;
+            }
+
+            return $this;
+        }
+
+        if (
+            is_null($alias) &&
+            is_null($conditions) &&
+            is_string($target) &&
+            $this->hasJoinAliasInternal('joins', $target)
+        ) {
+            return $this;
+        }
+
+        $params = [];
+
+        if ($noLeftAlias) {
+            $params['noLeftAlias'] = true;
+        }
+
+        if ($onlyMiddle) {
+            $params['onlyMiddle'] = true;
+        }
+
+        if ($isLateral) {
+            $params['isLateral'] = true;
+        }
+
+        $params['type'] = $joinType;
+
+        $this->params['joins'][] = [$target, $alias, $conditions, $params];
+
+        return $this;
+    }
+
+    private function hasJoinAliasInternal(string $type, string $alias): bool
+    {
+        $joins = $this->params[$type] ?? [];
+
+        if (in_array($alias, $joins)) {
+            return true;
+        }
+
+        foreach ($joins as $item) {
+            if (is_array($item) && count($item) > 1) {
+                if ($item[1] === $alias) {
+                    return true;
+                }
+
+                if (
+                    $item[1] === null &&
+                    $item[0] === $alias &&
+                    lcfirst($item[0]) === $alias
+                ) {
+                    return true;
+                }
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * @deprecated As of v9.2.0. Use `hasJoinAlias`.
+     */
+    public function hasLeftJoinAlias(string $alias): bool
+    {
+        return $this->hasJoinAlias($alias);
+    }
+
+    /**
+     * Whether an alias is in joins.
+     */
+    public function hasJoinAlias(string $alias): bool
+    {
+        return $this->hasJoinAliasInternal('joins', $alias) ||
+            // For bc.
+            $this->hasJoinAliasInternal('leftJoins', $alias);
+    }
+
+    /**
+     * @param array<Expression|mixed[]> $itemList
+     * @return array<array{0: string, 1?: string}|string>
+     */
+    private function normalizeExpressionItemArray(array $itemList): array
+    {
+        $resultList = [];
+
+        foreach ($itemList as $item) {
+            if ($item instanceof Expression) {
+                $resultList[] = $item->getValue();
+
+                continue;
+            }
+
+            if (!is_array($item) || !count($item) || !$item[0] instanceof Expression) {
+                /** @var array{0:string, 1?:string} $item */
+                $resultList[] = $item;
+
+                continue;
+            }
+
+            $newItem = [$item[0]->getValue()];
+
+            if (count($item) > 1) {
+                $newItem[] = $item[1];
+            }
+
+            /** @var array{0:string,1?:string} $newItem */
+
+            $resultList[] = $newItem;
+        }
+
+        return $resultList;
+    }
+
+    /**
+     * @param array<Order|mixed[]|string> $itemList
+     * @param string|bool|null $direction
+     * @return array<array{string, string|bool}>
+     */
+    private function normalizeOrderExpressionItemArray(array $itemList, $direction): array
+    {
+        $resultList = [];
+
+        foreach ($itemList as $item) {
+            if (is_string($item)) {
+                $resultList[] = [$item, $direction];
+
+                continue;
+            }
+
+            if (is_int($item)) {
+                $resultList[] = [(string) $item, $direction];
+
+                continue;
+            }
+
+            if ($item instanceof Order) {
+                $resultList[] = [
+                    $item->getExpression()->getValue(),
+                    $item->getDirection()
+                ];
+
+                continue;
+            }
+
+            if ($item instanceof Expression) {
+                $resultList[] = [
+                    $item->getValue(),
+                    $direction
+                ];
+
+                continue;
+            }
+
+            if (!is_array($item) || !count($item)) {
+                throw new RuntimeException("Bad order item.");
+            }
+
+            $itemValue = $item[0] instanceof Expression ?
+                $item[0]->getValue() :
+                $item[0];
+
+            if (!is_string($itemValue) && !is_int($itemValue)) {
+                throw new RuntimeException("Bad order item.");
+            }
+
+            $itemDirection = count($item) > 1 ? $item[1] : $direction;
+
+            if (is_bool($itemDirection)) {
+                $itemDirection = $itemDirection ?
+                    Order::DESC :
+                    Order::ASC;
+            }
+
+            $resultList[] = [$itemValue, $itemDirection];
+        }
+
+        return $resultList;
+    }
+}

application/Espo/ORM/Query/SelectingQuery.php

@@ -0,0 +1,33 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+interface SelectingQuery extends Query
+{}

application/Espo/ORM/Query/SelectingTrait.php

@@ -0,0 +1,146 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use Espo\ORM\Query\Part\Order;
+use Espo\ORM\Query\Part\WhereClause;
+use Espo\ORM\Query\Part\Join;
+
+use RuntimeException;
+
+trait SelectingTrait
+{
+    /**
+     * Get ORDER items.
+     *
+     * @return Order[]
+     */
+    public function getOrder(): array
+    {
+        return array_map(
+            function ($item) {
+                if (is_array($item) && count($item)) {
+                    $itemValue = is_int($item[0]) ? (string) $item[0] : $item[0];
+
+                    return Order::fromString($itemValue)
+                        ->withDirection($item[1] ?? Order::ASC);
+                }
+
+                if (is_string($item)) {
+                    return Order::fromString($item);
+                }
+
+                throw new RuntimeException("Bad order item.");
+            },
+            $this->params['orderBy'] ?? []
+        );
+    }
+
+    /**
+     * Get WHERE clause.
+     */
+    public function getWhere(): ?WhereClause
+    {
+        $whereClause = $this->params['whereClause'] ?? null;
+
+        if ($whereClause === null || $whereClause === []) {
+            return null;
+        }
+
+        $where = WhereClause::fromRaw($whereClause);
+
+        if (!$where instanceof WhereClause) {
+            throw new RuntimeException();
+        }
+
+        return $where;
+    }
+
+    /**
+     * Get JOIN items.
+     *
+     * @return Join[]
+     */
+    public function getJoins(): array
+    {
+        return array_map(
+            function ($item) {
+                if (is_string($item)) {
+                    $item = [$item];
+                }
+
+                $conditions = isset($item[2]) ?
+                    WhereClause::fromRaw($item[2]) : null;
+
+                $params = $item[3] ?? [];
+
+                $type = $params['type'] ?? null;
+                $type ??= Join\JoinType::inner;
+
+                return Join::create($item[0])
+                    ->withAlias($item[1] ?? null)
+                    ->withConditions($conditions)
+                    ->withType($type);
+            },
+            $this->params['joins'] ?? []
+        );
+    }
+
+    /**
+     * @return Join[]
+     * @deprecated As of 9.2.0. Use getJoins and check join type.
+     */
+    public function getLeftJoins(): array
+    {
+        return array_map(
+            function ($item) {
+                if (is_string($item)) {
+                    $item = [$item];
+                }
+
+                $conditions = isset($item[2]) ?
+                    WhereClause::fromRaw($item[2]) : null;
+
+                return Join::create($item[0])
+                    ->withAlias($item[1] ?? null)
+                    ->withConditions($conditions)
+                    ->withLeft();
+            },
+            $this->params['leftJoins'] ?? []
+        );
+    }
+
+    /**
+     * @param array<string, mixed> $params
+     */
+    private static function validateRawParamsSelecting(array $params): void
+    {
+    }
+}

application/Espo/ORM/Query/Union.php

@@ -0,0 +1,52 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use RuntimeException;
+
+/**
+ * Union parameters.
+ *
+ * Immutable.
+ */
+class Union implements SelectingQuery
+{
+    use BaseTrait;
+
+    /**
+     * @param array<string, mixed> $params
+     */
+    private function validateRawParams(array $params): void
+    {
+        if (empty($params['queries'])) {
+            throw new RuntimeException("Union params: No query were added.");
+        }
+    }
+}

application/Espo/ORM/Query/UnionBuilder.php

@@ -0,0 +1,146 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use Espo\ORM\Query\Part\Order;
+
+use InvalidArgumentException;
+
+class UnionBuilder implements Builder
+{
+    use BaseBuilderTrait;
+
+    /**
+     * Create an instance.
+     */
+    public static function create(): self
+    {
+        return new self();
+    }
+
+    /**
+     * Build a UNION select query.
+     */
+    public function build(): Union
+    {
+        return Union::fromRaw($this->params);
+    }
+
+    /**
+     * Clone an existing query for a subsequent modifying and building.
+     */
+    public function clone(Union $query): self
+    {
+        $this->cloneInternal($query);
+
+        return $this;
+    }
+
+    /**
+     * Use UNION ALL.
+     */
+    public function all(): self
+    {
+        $this->params['all'] = true;
+
+        return $this;
+    }
+
+    public function query(Select $query): self
+    {
+        $this->params['queries'] = $this->params['queries'] ?? [];
+        $this->params['queries'][] = $query;
+
+        return $this;
+    }
+
+    /**
+     * Apply OFFSET and LIMIT.
+     */
+    public function limit(?int $offset = null, ?int $limit = null): self
+    {
+        $this->params['offset'] = $offset;
+        $this->params['limit'] = $limit;
+
+        return $this;
+    }
+
+    /**
+     * Apply ORDER.
+     *
+     * @param string|array<array{string, (Order::ASC|Order::DESC)|bool}|array{string}> $orderBy A select alias.
+     * @param (Order::ASC|Order::DESC)|bool $direction A direction. True for DESC.
+     */
+    public function order($orderBy, string|bool $direction = Order::ASC): self
+    {
+        if (is_bool($direction)) {
+            $direction = $direction ? Order::DESC : Order::ASC;
+        }
+
+        if (!$orderBy) {
+            throw new InvalidArgumentException();
+        }
+
+        if (is_array($orderBy)) {
+            foreach ($orderBy as $item) {
+                /** @var mixed[] $item */
+
+                if (count($item) === 2) {
+                    /** @var array{string, bool|(Order::ASC|Order::DESC)} $item */
+                    $this->order($item[0], $item[1]);
+
+                    continue;
+                }
+
+                if (count($item) === 1) {
+                    /** @var array{string} $item */
+                    $this->order($item[0]);
+
+                    continue;
+                }
+
+                throw new InvalidArgumentException("Bad order.");
+            }
+
+            return $this;
+        }
+
+        /** @var object|scalar $orderBy */
+
+        if (!is_string($orderBy) && !is_int($orderBy)) {
+            throw new InvalidArgumentException("Bad order.");
+        }
+
+        $this->params['orderBy'] = $this->params['orderBy'] ?? [];
+        $this->params['orderBy'][] = [$orderBy, $direction];
+
+        return $this;
+    }
+}

application/Espo/ORM/Query/Update.php

@@ -0,0 +1,109 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use Espo\ORM\Query\Part\Expression;
+use RuntimeException;
+
+/**
+ * Update parameters.
+ *
+ * Immutable.
+ */
+class Update implements Query
+{
+    use SelectingTrait;
+    use BaseTrait;
+
+    /**
+     * Get an entity type.
+     */
+    public function getIn(): string
+    {
+        $in = $this->params['from'];
+
+        if ($in === null) {
+            throw new RuntimeException("Missing 'in'.");
+        }
+
+        return $in;
+    }
+
+    /**
+     * Get a LIMIT.
+     */
+    public function getLimit(): ?int
+    {
+        return $this->params['limit'] ?? null;
+    }
+
+    /**
+     * Get SET values.
+     *
+     * @return array<string, scalar|Expression|null>
+     */
+    public function getSet(): array
+    {
+        $set = [];
+        /** @var array<string, ?scalar> $raw */
+        $raw = $this->params['set'];
+
+        foreach ($raw as $key => $value) {
+            if (str_ends_with($key, ':')) {
+                $key = substr($key, 0, -1);
+                $value = Expression::create((string) $value);
+            }
+
+            $set[$key] = $value;
+        }
+
+        return $set;
+    }
+
+    /**
+     * @param array<string, mixed> $params
+     */
+    private function validateRawParams(array $params): void
+    {
+        $this->validateRawParamsSelecting($params);
+
+        $from = $params['from'] ?? null;
+
+        if (!$from || !is_string($from)) {
+            throw new RuntimeException("Update params: Missing 'in'.");
+        }
+
+        $set = $params['set'] ?? null;
+
+        if (!$set || !is_array($set)) {
+            throw new RuntimeException("Update params: Bad or missing 'set' parameter.");
+        }
+    }
+}

application/Espo/ORM/Query/UpdateBuilder.php

@@ -0,0 +1,114 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Query;
+
+use Espo\ORM\Query\Part\Expression;
+use RuntimeException;
+
+class UpdateBuilder implements Builder
+{
+    use SelectingBuilderTrait;
+
+    /**
+     * Create an instance.
+     */
+    public static function create(): self
+    {
+        return new self();
+    }
+
+    /**
+     * Build a UPDATE query.
+     */
+    public function build(): Update
+    {
+        return Update::fromRaw($this->params);
+    }
+
+    /**
+     * Clone an existing query for a subsequent modifying and building.
+     */
+    public function clone(Update $query): self
+    {
+        $this->cloneInternal($query);
+
+        return $this;
+    }
+
+    /**
+     * For what entity type to build a query.
+     */
+    public function in(string $entityType): self
+    {
+        if (isset($this->params['from'])) {
+            throw new RuntimeException("Method 'in' can be called only once.");
+        }
+
+        $this->params['from'] = $entityType;
+
+        return $this;
+    }
+
+    /**
+     * Values to set. Column => Value map.
+     *
+     * @param array<string, scalar|Expression|null> $set
+     */
+    public function set(array $set): self
+    {
+        $modified = [];
+
+        foreach ($set as $key => $value) {
+            if (!$value instanceof Expression) {
+                $modified[$key] = $value;
+
+                continue;
+            }
+
+            $newKey = rtrim($key, ':')  . ':';
+
+            $modified[$newKey] = $value->getValue();
+        }
+
+        $this->params['set'] = $modified;
+
+        return $this;
+    }
+
+    /**
+     * Apply LIMIT.
+     */
+    public function limit(?int $limit = null): self
+    {
+        $this->params['limit'] = $limit;
+
+        return $this;
+    }
+}

application/Espo/ORM/QueryBuilder.php

@@ -0,0 +1,140 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM;
+
+use Espo\ORM\Query\Delete;
+use Espo\ORM\Query\DeleteBuilder;
+use Espo\ORM\Query\Insert;
+use Espo\ORM\Query\InsertBuilder;
+use Espo\ORM\Query\Part\Expression;
+use Espo\ORM\Query\Part\Selection;
+use Espo\ORM\Query\Query;
+use Espo\ORM\Query\Select;
+use Espo\ORM\Query\SelectBuilder;
+use Espo\ORM\Query\Union;
+use Espo\ORM\Query\UnionBuilder;
+use Espo\ORM\Query\Update;
+use Espo\ORM\Query\UpdateBuilder;
+
+use RuntimeException;
+
+/**
+ * Creates query builders for specific query types.
+ */
+class QueryBuilder
+{
+    /**
+     * Specify SELECT. Columns and expressions to be selected. If not called, then
+     * all entity attributes will be selected. Passing an array will reset
+     * previously set items. Passing a SelectExpression|Expression|string will append the item.
+     *
+     * Usage options:
+     * * `select(SelectExpression $expression)`
+     * * `select([$expr1, $expr2, ...])`
+     * * `select(string $expression, string $alias)`
+     *
+     * @param Selection|Selection[]|Expression|string[]|string $select
+     * An array of expressions or one expression.
+     * @param ?string $alias An alias. Actual if the first parameter is not an array.
+     */
+    public function select($select = null, ?string $alias = null): SelectBuilder
+    {
+        $builder = new SelectBuilder();
+
+        if ($select === null) {
+            return $builder;
+        }
+
+        return $builder->select($select, $alias);
+    }
+
+    /**
+     * Proceed with UPDATE builder.
+     */
+    public function update(): UpdateBuilder
+    {
+        return new UpdateBuilder();
+    }
+
+    /**
+     * Proceed with DELETE builder.
+     */
+    public function delete(): DeleteBuilder
+    {
+        return new DeleteBuilder();
+    }
+
+    /**
+     * Proceed with INSERT builder.
+     */
+    public function insert(): InsertBuilder
+    {
+        return new InsertBuilder();
+    }
+
+    /**
+     * Proceed with UNION builder.
+     */
+    public function union(): UnionBuilder
+    {
+        return new UnionBuilder();
+    }
+
+    /**
+     * Clone an existing query and proceed modifying it.
+     *
+     * @return SelectBuilder|UpdateBuilder|DeleteBuilder|InsertBuilder|UnionBuilder
+     * @throws RuntimeException
+     */
+    public function clone(Query $query): SelectBuilder|UpdateBuilder|DeleteBuilder|InsertBuilder|UnionBuilder
+    {
+        if ($query instanceof Select) {
+            return $this->select()->clone($query);
+        }
+
+        if ($query instanceof Update) {
+            return $this->update()->clone($query);
+        }
+
+        if ($query instanceof Delete) {
+            return $this->delete()->clone($query);
+        }
+
+        if ($query instanceof Insert) {
+            return $this->insert()->clone($query);
+        }
+
+        if ($query instanceof Union) {
+            return $this->union()->clone($query);
+        }
+
+        throw new RuntimeException("Can't clone an unsupported query.");
+    }
+}

application/Espo/ORM/QueryComposer/Functions.php

@@ -0,0 +1,165 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\QueryComposer;
+
+/**
+ * @internal
+ */
+class Functions
+{
+    public const FUNCTION_LIST = [
+        'ROW',
+        'COUNT',
+        'SUM',
+        'AVG',
+        'MAX',
+        'MIN',
+        'DATE',
+        'MONTH',
+        'DAY',
+        'YEAR',
+        'WEEK',
+        'WEEK_0',
+        'WEEK_1',
+        'QUARTER',
+        'DAYOFMONTH',
+        'DAYOFWEEK',
+        'DAYOFWEEK_NUMBER',
+        'MONTH_NUMBER',
+        'DATE_NUMBER',
+        'YEAR_NUMBER',
+        'HOUR_NUMBER',
+        'HOUR',
+        'MINUTE_NUMBER',
+        'MINUTE',
+        'QUARTER_NUMBER',
+        'WEEK_NUMBER',
+        'WEEK_NUMBER_0',
+        'WEEK_NUMBER_1',
+        'LOWER',
+        'UPPER',
+        'TRIM',
+        'REPLACE',
+        'LENGTH',
+        'CHAR_LENGTH',
+        'YEAR_0',
+        'YEAR_1',
+        'YEAR_2',
+        'YEAR_3',
+        'YEAR_4',
+        'YEAR_5',
+        'YEAR_6',
+        'YEAR_7',
+        'YEAR_8',
+        'YEAR_9',
+        'YEAR_10',
+        'YEAR_11',
+        'QUARTER_0',
+        'QUARTER_1',
+        'QUARTER_2',
+        'QUARTER_3',
+        'QUARTER_4',
+        'QUARTER_5',
+        'QUARTER_6',
+        'QUARTER_7',
+        'QUARTER_8',
+        'QUARTER_9',
+        'QUARTER_10',
+        'QUARTER_11',
+        'CONCAT',
+        'LEFT',
+        'TZ',
+        'NOW',
+        'ADD',
+        'SUB',
+        'MUL',
+        'DIV',
+        'MOD',
+        'FLOOR',
+        'CEIL',
+        'ROUND',
+        'GREATEST',
+        'LEAST',
+        'COALESCE',
+        'IF',
+        'LIKE',
+        'NOT_LIKE',
+        'EQUAL',
+        'NOT_EQUAL',
+        'GREATER_THAN',
+        'LESS_THAN',
+        'GREATER_THAN_OR_EQUAL',
+        'LESS_THAN_OR_EQUAL',
+        'IS_NULL',
+        'IS_NOT_NULL',
+        'OR',
+        'AND',
+        'NOT',
+        'IN',
+        'NOT_IN',
+        'IFNULL',
+        'NULLIF',
+        'SWITCH',
+        'MAP',
+        'BINARY',
+        'MD5',
+        'UNIX_TIMESTAMP',
+        'TIMESTAMPDIFF_DAY',
+        'TIMESTAMPDIFF_MONTH',
+        'TIMESTAMPDIFF_YEAR',
+        'TIMESTAMPDIFF_WEEK',
+        'TIMESTAMPDIFF_HOUR',
+        'TIMESTAMPDIFF_MINUTE',
+        'TIMESTAMPDIFF_SECOND',
+        'POSITION_IN_LIST',
+        'MATCH_BOOLEAN',
+        'MATCH_NATURAL_LANGUAGE',
+        'ANY_VALUE',
+    ];
+
+    public const COMPARISON_FUNCTION_LIST = [
+        'LIKE',
+        'NOT_LIKE',
+        'EQUAL',
+        'NOT_EQUAL',
+        'GREATER_THAN',
+        'LESS_THAN',
+        'GREATER_THAN_OR_EQUAL',
+        'LESS_THAN_OR_EQUAL',
+    ];
+
+    public const MATH_OPERATION_FUNCTION_LIST = [
+        'ADD',
+        'SUB',
+        'MUL',
+        'DIV',
+        'MOD',
+    ];
+}

application/Espo/ORM/QueryComposer/MysqlQueryComposer.php

@@ -0,0 +1,101 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\QueryComposer;
+
+use Espo\ORM\Query\LockTable as LockTableQuery;
+
+use LogicException;
+
+class MysqlQueryComposer extends BaseQueryComposer
+{
+    public function composeLockTable(LockTableQuery $query): string
+    {
+        $params = $query->getRaw();
+
+        $entityType = $this->sanitize($params['table']);
+
+        $table = $this->toDb($entityType);
+
+        $mode = $params['mode'];
+
+        if (empty($table)) {
+            throw new LogicException();
+        }
+
+        if (!in_array($mode, [LockTableQuery::MODE_SHARE, LockTableQuery::MODE_EXCLUSIVE])) {
+            throw new LogicException();
+        }
+
+        $sql = "LOCK TABLES " . $this->quoteIdentifier($table) . " ";
+
+        $modeMap = [
+            LockTableQuery::MODE_SHARE => 'READ',
+            LockTableQuery::MODE_EXCLUSIVE => 'WRITE',
+        ];
+
+        $sql .= $modeMap[$mode];
+
+        if (str_contains($table, '_')) {
+            // MySQL has an issue that aliased tables must be locked with alias.
+            $sql .= ", " .
+                $this->quoteIdentifier($table) . " AS " .
+                $this->quoteIdentifier(lcfirst($entityType)) . " " . $modeMap[$mode];
+        }
+
+        return $sql;
+    }
+
+    public function composeUnlockTables(): string
+    {
+        return "UNLOCK TABLES";
+    }
+
+    protected function limit(string $sql, ?int $offset = null, ?int $limit = null): string
+    {
+        if (!is_null($offset) && !is_null($limit)) {
+            $offset = intval($offset);
+            $limit = intval($limit);
+
+            $sql .= " LIMIT $offset, $limit";
+
+            return $sql;
+        }
+
+        if (!is_null($limit)) {
+            $limit = intval($limit);
+
+            $sql .= " LIMIT $limit";
+
+            return $sql;
+        }
+
+        return $sql;
+    }
+}

application/Espo/ORM/QueryComposer/Part/FunctionConverter.php

@@ -0,0 +1,35 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\QueryComposer\Part;
+
+interface FunctionConverter
+{
+    public function convert(string ...$argumentList): string;
+}

application/Espo/ORM/QueryComposer/Part/FunctionConverterFactory.php

@@ -0,0 +1,37 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\QueryComposer\Part;
+
+interface FunctionConverterFactory
+{
+    public function create(string $name): FunctionConverter;
+
+    public function isCreatable(string $name): bool;
+}

application/Espo/ORM/QueryComposer/PostgresqlQueryComposer.php

@@ -0,0 +1,656 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\QueryComposer;
+
+use Espo\ORM\Entity;
+use Espo\ORM\Name\Attribute;
+use Espo\ORM\Query\Delete as DeleteQuery;
+use Espo\ORM\Query\DeleteBuilder;
+use Espo\ORM\Query\Insert as InsertQuery;
+use Espo\ORM\Query\LockTable as LockTableQuery;
+
+use Espo\ORM\Query\Part\Condition as Cond;
+use Espo\ORM\Query\SelectBuilder;
+use Espo\ORM\Query\Update as UpdateQuery;
+use Espo\ORM\Query\UpdateBuilder;
+use LogicException;
+use RuntimeException;
+
+class PostgresqlQueryComposer extends BaseQueryComposer
+{
+    protected string $identifierQuoteCharacter = '"';
+    protected bool $indexHints = false;
+    protected bool $skipForeignIfForUpdate = true;
+    protected int $aliasMaxLength = 128;
+
+    /** @var array<string, string> */
+    protected array $comparisonOperatorMap = [
+        '!=s' => 'NOT IN',
+        '=s' => 'IN',
+        '!=' => '<>',
+        '!*' => 'NOT ILIKE',
+        '*' => 'ILIKE',
+        '>=any' => '>= ANY',
+        '<=any' => '<= ANY',
+        '>any' => '> ANY',
+        '<any' => '< ANY',
+        '!=any' => '<> ANY',
+        '=any' => '= ANY',
+        '>=all' => '>= ALL',
+        '<=all' => '<= ALL',
+        '>all' => '> ALL',
+        '<all' => '< ALL',
+        '!=all' => '<> ALL',
+        '=all' => '= ALL',
+    ];
+
+    /** @var array<string, string> */
+    protected array $comparisonFunctionOperatorMap = [
+        'LIKE' => 'ILIKE',
+        'NOT_LIKE' => 'NOT ILIKE',
+        'EQUAL' => '=',
+        'NOT_EQUAL' => '<>',
+        'GREATER_THAN' => '>',
+        'LESS_THAN' => '<',
+        'GREATER_THAN_OR_EQUAL' => '>=',
+        'LESS_THAN_OR_EQUAL' => '<=',
+        'IS_NULL' => 'IS NULL',
+        'IS_NOT_NULL' => 'IS NOT NULL',
+        'IN' => 'IN',
+        'NOT_IN' => 'NOT IN',
+    ];
+
+    protected function quoteColumn(string $column): string
+    {
+        $list = explode('.', $column);
+        $list = array_map(fn ($item) => '"' . $item . '"', $list);
+
+        return implode('.', $list);
+    }
+
+    /**
+     * @todo Make protected.
+     *
+     * @param mixed $value
+     */
+    public function quote($value): string
+    {
+        if (is_null($value)) {
+            return 'NULL';
+        }
+
+        if (is_bool($value)) {
+            return $value ? 'true' : 'false';
+        }
+
+        if (is_int($value)) {
+            return strval($value);
+        }
+
+        if (is_float($value)) {
+            return strval($value);
+        }
+
+        return $this->pdo->quote($value);
+    }
+
+    /**
+     * @param string[] $argumentPartList
+     * @param array<string, mixed> $params
+     */
+    protected function getFunctionPart(
+        string $function,
+        string $part,
+        array $params,
+        string $entityType,
+        bool $distinct,
+        array $argumentPartList = []
+    ): string {
+
+        if (in_array($function, ['MATCH_BOOLEAN', 'MATCH_NATURAL_LANGUAGE'])) {
+            if (count($argumentPartList) < 2) {
+                throw new RuntimeException("Not enough arguments for MATCH function.");
+            }
+
+            $queryPart = end($argumentPartList);
+            $columnsPart = implode(
+                " || ' ' || ",
+                array_map(
+                    fn ($item) => "COALESCE($item, '')",
+                    array_slice($argumentPartList, 0, -1)
+                )
+            );
+
+            return "TS_RANK_CD(TO_TSVECTOR($columnsPart), PLAINTO_TSQUERY($queryPart))";
+        }
+
+        if ($function === 'IF') {
+            if (count($argumentPartList) < 3) {
+                throw new RuntimeException("Not enough arguments for IF function.");
+            }
+
+            $conditionPart = $argumentPartList[0];
+            $thenPart = $argumentPartList[1];
+            $elsePart = $argumentPartList[2];
+
+            return "CASE WHEN $conditionPart THEN $thenPart ELSE $elsePart END";
+        }
+
+        if ($function === 'ROUND') {
+            if (count($argumentPartList) === 2 && $argumentPartList[1] === '0') {
+                $argumentPartList = array_slice($argumentPartList, 0, -1);
+
+                return "ROUND($argumentPartList[0])";
+            }
+        }
+
+        if ($function === 'UNIX_TIMESTAMP') {
+            $arg = $argumentPartList[0] ?? 'NOW()';
+
+            return "FLOOR(EXTRACT(EPOCH FROM $arg))";
+        }
+
+        if ($function === 'BINARY') {
+            // Not supported.
+            return $argumentPartList[0] ?? '0';
+        }
+
+        if ($function === 'TZ') {
+            if (count($argumentPartList) < 2) {
+                throw new RuntimeException("Not enough arguments for function TZ.");
+            }
+
+            $offsetHoursString = $argumentPartList[1];
+            if (str_starts_with($offsetHoursString, '\'') && str_ends_with($offsetHoursString, '\'')) {
+                $offsetHoursString = substr($offsetHoursString, 1, -1);
+            }
+
+            if (str_contains($offsetHoursString, '.')) {
+                $minutes = (int) (floatval($offsetHoursString) * 60);
+                $minutesString = (string) $minutes;
+
+                return "$argumentPartList[0] + INTERVAL '$minutesString MINUTE'";
+            }
+
+            return "$argumentPartList[0] + INTERVAL '$offsetHoursString HOUR'";
+        }
+
+        if ($function === 'POSITION_IN_LIST') {
+            if (count($argumentPartList) <= 1) {
+                return $this->quote(1);
+            }
+
+            $field = $argumentPartList[0];
+
+            $pairs = array_map(
+                fn($i) => [$i, $argumentPartList[$i]],
+                array_keys($argumentPartList)
+            );
+
+            $whenParts = array_map(function ($item) use ($field) {
+                $resolution = intval($item[0]);
+                $value = $item[1];
+
+                return " WHEN $field = $value THEN $resolution";
+            }, array_slice($pairs, 1));
+
+            return "CASE" . implode('', $whenParts) . " ELSE 0 END";
+        }
+
+        if ($function === 'IFNULL') {
+            $function = 'COALESCE';
+        }
+
+        if (str_starts_with($function, 'YEAR_') && $function !== 'YEAR_NUMBER') {
+            $fiscalShift = substr($function, 5);
+
+            if (is_numeric($fiscalShift)) {
+                $fiscalShift = (int) $fiscalShift;
+                $fiscalFirstMonth = $fiscalShift + 1;
+
+                return
+                    "CASE WHEN EXTRACT(MONTH FROM $part) >= $fiscalFirstMonth THEN ".
+                    "EXTRACT(YEAR FROM $part) ".
+                    "ELSE EXTRACT(YEAR FROM $part) - 1 END";
+            }
+        }
+
+        if (str_starts_with($function, 'QUARTER_') && $function !== 'QUARTER_NUMBER') {
+            $fiscalShift = substr($function, 8);
+
+            if (is_numeric($fiscalShift)) {
+                $fiscalShift = (int) $fiscalShift;
+                $fiscalFirstMonth = $fiscalShift + 1;
+                $fiscalDistractedMonth = $fiscalFirstMonth < 4 ?
+                    12 - $fiscalFirstMonth :
+                    12 - $fiscalFirstMonth + 1;
+
+                return
+                    "CASE WHEN EXTRACT(MONTH FROM $part) >= $fiscalFirstMonth " .
+                    "THEN " .
+                    "CONCAT(" .
+                    "EXTRACT(YEAR FROM $part), '_', " .
+                    "FLOOR((EXTRACT(MONTH FROM $part) - $fiscalFirstMonth) / 3) + 1" .
+                    ") " .
+                    "ELSE " .
+                    "CONCAT(" .
+                    "EXTRACT(YEAR FROM $part) - 1, '_', " .
+                    "CEIL((EXTRACT(MONTH FROM $part) + $fiscalDistractedMonth) / 3)" .
+                    ") " .
+                    "END";
+            }
+        }
+
+        switch ($function) {
+            case 'MONTH':
+                return "TO_CHAR($part, 'YYYY-MM')";
+
+            case 'DAY':
+                return "TO_CHAR($part, 'YYYY-MM-DD')";
+
+            case 'WEEK':
+            case 'WEEK_0':
+            case 'WEEK_1':
+                if (str_starts_with($part, "'")) {
+                    $part = "DATE " . $part;
+                }
+
+                return "CONCAT(TO_CHAR($part, 'YYYY'), '/', TRIM(LEADING '0' FROM TO_CHAR($part, 'IW')))";
+
+            case 'QUARTER':
+                return "CONCAT(TO_CHAR($part, 'YYYY'), '_', TO_CHAR($part, 'Q'))";
+
+            case 'WEEK_NUMBER_0':
+            case 'WEEK_NUMBER':
+            case 'WEEK_NUMBER_1':
+                // Monday week-start not implemented.
+                return "TO_CHAR($part, 'IW')::INTEGER";
+
+            case 'HOUR_NUMBER':
+            case 'HOUR':
+                return "EXTRACT(HOUR FROM $part)";
+
+            case 'MINUTE_NUMBER':
+            case 'MINUTE':
+                return "EXTRACT(MINUTE FROM $part)";
+
+            case 'SECOND_NUMBER':
+            case 'SECOND':
+                return "FLOOR(EXTRACT(SECOND FROM $part))";
+
+            case 'DATE_NUMBER':
+            case 'DAYOFMONTH':
+                return "EXTRACT(DAY FROM $part)";
+
+            case 'DAYOFWEEK_NUMBER':
+            case 'DAYOFWEEK':
+                return "EXTRACT(DOW FROM $part)";
+
+            case 'MONTH_NUMBER':
+                return "EXTRACT(MONTH FROM $part)";
+
+            case 'YEAR_NUMBER':
+            case 'YEAR':
+                return "EXTRACT(YEAR FROM $part)";
+
+            case 'QUARTER_NUMBER':
+                return "EXTRACT(QUARTER FROM $part)";
+        }
+
+        if (str_starts_with($function, 'TIMESTAMPDIFF_')) {
+            $from = $argumentPartList[0] ?? $this->quote(0);
+            $to = $argumentPartList[1] ?? $this->quote(0);
+
+            switch ($function) {
+                case 'TIMESTAMPDIFF_YEAR':
+                    return "EXTRACT(YEAR FROM $to - $from)";
+
+                case 'TIMESTAMPDIFF_MONTH':
+                    return "EXTRACT(MONTH FROM $to - $from)";
+
+                case 'TIMESTAMPDIFF_WEEK':
+                    return "FLOOR(EXTRACT(DAY FROM $to - $from) / 7)";
+
+                case 'TIMESTAMPDIFF_DAY':
+                    return "EXTRACT(DAY FROM ($to) - $from)";
+
+                case 'TIMESTAMPDIFF_HOUR':
+                    return "EXTRACT(HOUR FROM $to - $from)";
+
+                case 'TIMESTAMPDIFF_MINUTE':
+                    return "EXTRACT(MINUTE FROM $to - $from)";
+
+                case 'TIMESTAMPDIFF_SECOND':
+                    return "FLOOR(EXTRACT(SECOND FROM $to - $from))";
+            }
+        }
+
+        return parent::getFunctionPart(
+            $function,
+            $part,
+            $params,
+            $entityType,
+            $distinct,
+            $argumentPartList
+        );
+    }
+
+    public function composeDelete(DeleteQuery $query): string
+    {
+        if (
+            $query->getJoins() !== [] ||
+            $query->getLeftJoins() !== [] ||
+            $query->getLimit() !== null ||
+            $query->getOrder() !== []
+        ) {
+            $subQueryBuilder = SelectBuilder::create()
+                ->select(Attribute::ID)
+                ->from($query->getFrom())
+                ->order($query->getOrder());
+
+            foreach ($query->getJoins() as $join) {
+                $subQueryBuilder->join($join);
+            }
+
+            foreach ($query->getLeftJoins() as $join) {
+                $subQueryBuilder->leftJoin($join);
+            }
+
+            if ($query->getWhere()) {
+                $subQueryBuilder->where($query->getWhere());
+            }
+
+            if ($query->getLimit() !== null) {
+                $subQueryBuilder->limit(null, $query->getLimit());
+            }
+
+            $builder = DeleteBuilder::create()
+                ->from($query->getFrom(), $query->getFromAlias())
+                ->where(
+                    Cond::in(
+                        Cond::column(Attribute::ID),
+                        $subQueryBuilder->build()
+                    )
+                );
+
+            $query = $builder->build();
+        }
+
+        return parent::composeDelete($query);
+    }
+
+    public function composeUpdate(UpdateQuery $query): string
+    {
+        if (
+            $query->getJoins() !== [] ||
+            $query->getLeftJoins() !== [] ||
+            $query->getLimit() !== null ||
+            $query->getOrder() !== []
+        ) {
+            $subQueryBuilder = SelectBuilder::create()
+                ->select(Attribute::ID)
+                ->from($query->getIn())
+                ->order($query->getOrder())
+                ->forUpdate();
+
+            foreach ($query->getJoins() as $join) {
+                $subQueryBuilder->join($join);
+            }
+
+            foreach ($query->getLeftJoins() as $join) {
+                $subQueryBuilder->leftJoin($join);
+            }
+
+            if ($query->getWhere()) {
+                $subQueryBuilder->where($query->getWhere());
+            }
+
+            if ($query->getLimit() !== null) {
+                $subQueryBuilder->limit(null, $query->getLimit());
+            }
+
+            $builder = UpdateBuilder::create()
+                ->in($query->getIn())
+                ->set($query->getSet())
+                ->where(
+                    Cond::in(
+                        Cond::column(Attribute::ID),
+                        $subQueryBuilder->build()
+                    )
+                );
+
+            $query = $builder->build();
+        }
+
+        return parent::composeUpdate($query);
+    }
+
+    public function composeInsert(InsertQuery $query): string
+    {
+        $params = $query->getRaw();
+        $params = $this->normalizeInsertParams($params);
+
+        $entityType = $params['into'];
+        $columns = $params['columns'];
+        $updateSet = $params['updateSet'];
+
+        $columnsPart = $this->getInsertColumnsPart($columns);
+        $valuesPart = $this->getInsertValuesPart($entityType, $params);
+        $updatePart = $updateSet ? $this->getInsertUpdatePart($updateSet) : null;
+
+        $table = $this->toDb($entityType);
+
+        $sql = "INSERT INTO " . $this->quoteIdentifier($table) . " ($columnsPart) $valuesPart";
+
+        if ($updatePart) {
+            $updateColumnsPart = implode(', ',
+                array_map(fn ($item) => $this->quoteIdentifier($this->toDb($this->sanitize($item))),
+                    $this->getEntityUniqueColumns($entityType)
+                )
+            );
+
+            $sql .= " ON CONFLICT($updateColumnsPart) DO UPDATE SET " . $updatePart;
+        }
+
+        return $sql;
+    }
+
+    /**
+     * @return string[]
+     */
+    private function getEntityUniqueColumns(string $entityType): array
+    {
+        $indexes = $this->metadata
+            ->getDefs()
+            ->getEntity($entityType)
+            ->getIndexList();
+
+        foreach ($indexes as $index) {
+            if ($index->isUnique()) {
+                return $index->getColumnList();
+            }
+        }
+
+        return [Attribute::ID];
+    }
+
+    /**
+     * @param array<string, mixed> $values
+     * @param array<string, mixed> $params
+     */
+    protected function getSetPart(Entity $entity, array $values, array $params): string
+    {
+        if (!count($values)) {
+            throw new RuntimeException("ORM Query: No SET values for update query.");
+        }
+
+        $list = [];
+
+        foreach ($values as $attribute => $value) {
+            $isNotValue = false;
+
+            if (str_ends_with($attribute, ':')) {
+                $attribute = substr($attribute, 0, -1);
+                $isNotValue = true;
+            }
+
+            if (strpos($attribute, '.') > 0) {
+                [$alias, $attribute] = explode('.', $attribute);
+
+                $alias = $this->sanitize($alias);
+                $column = $this->toDb($this->sanitize($attribute));
+
+                $left = $this->quoteColumn("{$alias}.{$column}");
+            } else {
+                $column = $this->toDb($this->sanitize($attribute));
+
+                $left = $this->quoteColumn("{$column}"); // Diff.
+            }
+
+            $right = $isNotValue ?
+                $this->convertComplexExpression($entity, $value, false, $params) :
+                $this->quote($value);
+
+            $list[] = $left . " = " . $right;
+        }
+
+        return implode(', ', $list);
+    }
+
+    public function composeRollbackToSavepoint(string $savepointName): string
+    {
+        return 'ROLLBACK TRANSACTION TO SAVEPOINT ' . $this->sanitize($savepointName);
+    }
+
+    public function composeLockTable(LockTableQuery $query): string
+    {
+        $params = $query->getRaw();
+
+        $table = $this->toDb($this->sanitize($params['table']));
+
+        $mode = $params['mode'];
+
+        if (empty($table)) {
+            throw new LogicException();
+        }
+
+        if (!in_array($mode, [LockTableQuery::MODE_SHARE, LockTableQuery::MODE_EXCLUSIVE])) {
+            throw new LogicException();
+        }
+
+        $sql = "LOCK TABLE " . $this->quoteIdentifier($table) . " IN ";
+
+        $modeMap = [
+            LockTableQuery::MODE_SHARE => 'SHARE',
+            LockTableQuery::MODE_EXCLUSIVE => 'EXCLUSIVE',
+        ];
+
+        $sql .= $modeMap[$mode] . " MODE";
+
+        return $sql;
+    }
+
+    protected function limit(string $sql, ?int $offset = null, ?int $limit = null): string
+    {
+        if (!is_null($offset) && !is_null($limit)) {
+            $offset = intval($offset);
+            $limit = intval($limit);
+
+            $sql .= " LIMIT $limit OFFSET $offset";
+
+            return $sql;
+        }
+
+        if (!is_null($limit)) {
+            $limit = intval($limit);
+
+            $sql .= " LIMIT $limit";
+
+            return $sql;
+        }
+
+        return $sql;
+    }
+
+    /**
+     * @param array<string, mixed> $params
+     */
+    protected function getSelectTailPart(array $params): ?string
+    {
+        $forShare = $params['forShare'] ?? null;
+        $forUpdate = $params['forUpdate'] ?? null;
+
+        if ($forShare) {
+            return "FOR SHARE";
+        }
+
+        if ($forUpdate) {
+            return "FOR UPDATE";
+        }
+
+        return null;
+    }
+
+    protected function composeDeleteQuery(
+        string $table,
+        ?string $alias,
+        string $where,
+        ?string $joins,
+        ?string $order,
+        ?int $limit
+    ): string {
+
+        $sql = "DELETE ";
+
+        $sql .= "FROM " . $this->quoteIdentifier($table);
+
+        if ($alias) {
+            $sql .= " AS " . $this->quoteIdentifier($alias);
+        }
+
+        if ($joins) {
+            $sql .= " $joins";
+        }
+
+        if ($where) {
+            $sql .= " WHERE $where";
+        }
+
+        if ($order) {
+            $sql .= " ORDER BY $order";
+        }
+
+        if ($limit !== null) {
+            $sql = $this->limit($sql, null, $limit);
+        }
+
+        return $sql;
+    }
+}

application/Espo/ORM/QueryComposer/QueryComposer.php

@@ -0,0 +1,58 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\QueryComposer;
+
+use Espo\ORM\Query\Select as SelectQuery;
+use Espo\ORM\Query\Update as UpdateQuery;
+use Espo\ORM\Query\Insert as InsertQuery;
+use Espo\ORM\Query\Delete as DeleteQuery;
+use Espo\ORM\Query\Union as UnionQuery;
+use Espo\ORM\Query\LockTable as LockTableQuery;
+
+interface QueryComposer
+{
+    public function composeSelect(SelectQuery $query): string;
+
+    public function composeUpdate(UpdateQuery $query): string;
+
+    public function composeDelete(DeleteQuery $query): string;
+
+    public function composeInsert(InsertQuery $query): string;
+
+    public function composeUnion(UnionQuery $query): string;
+
+    public function composeLockTable(LockTableQuery $query): string;
+
+    public function composeCreateSavepoint(string $savepointName): string;
+
+    public function composeReleaseSavepoint(string $savepointName): string;
+
+    public function composeRollbackToSavepoint(string $savepointName): string;
+}

application/Espo/ORM/QueryComposer/QueryComposerFactory.php

@@ -0,0 +1,35 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\QueryComposer;
+
+interface QueryComposerFactory
+{
+    public function create(string $platform): QueryComposer;
+}

application/Espo/ORM/QueryComposer/QueryComposerWrapper.php

@@ -0,0 +1,127 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\QueryComposer;
+
+use Espo\ORM\Query\Query as Query;
+use Espo\ORM\Query\Select as SelectQuery;
+use Espo\ORM\Query\Update as UpdateQuery;
+use Espo\ORM\Query\Insert as InsertQuery;
+use Espo\ORM\Query\Delete as DeleteQuery;
+use Espo\ORM\Query\Union as UnionQuery;
+use Espo\ORM\Query\LockTable as LockTableQuery;
+
+use RuntimeException;
+
+class QueryComposerWrapper implements QueryComposer
+{
+    private QueryComposer $queryComposer;
+
+    public function __construct(QueryComposer $queryComposer)
+    {
+        $this->queryComposer = $queryComposer;
+    }
+
+    /**
+     * Compose an SQL query.
+     */
+    public function compose(Query $query): string
+    {
+        if ($query instanceof SelectQuery) {
+            return $this->composeSelect($query);
+        }
+
+        if ($query instanceof UpdateQuery) {
+            return $this->composeUpdate($query);
+        }
+
+        if ($query instanceof InsertQuery) {
+            return $this->composeInsert($query);
+        }
+
+        if ($query instanceof DeleteQuery) {
+            return $this->composeDelete($query);
+        }
+
+        if ($query instanceof UnionQuery) {
+            return $this->composeUnion($query);
+        }
+
+        if ($query instanceof LockTableQuery) {
+            return $this->composeLockTable($query);
+        }
+
+        throw new RuntimeException("ORM Query: Unknown query type passed.");
+    }
+
+    public function composeSelect(SelectQuery $query): string
+    {
+        return $this->queryComposer->composeSelect($query);
+    }
+
+    public function composeUpdate(UpdateQuery $query): string
+    {
+        return $this->queryComposer->composeUpdate($query);
+    }
+
+    public function composeDelete(DeleteQuery $query): string
+    {
+        return $this->queryComposer->composeDelete($query);
+    }
+
+    public function composeInsert(InsertQuery $query): string
+    {
+        return $this->queryComposer->composeInsert($query);
+    }
+
+    public function composeUnion(UnionQuery $query): string
+    {
+        return $this->queryComposer->composeUnion($query);
+    }
+
+    public function composeLockTable(LockTableQuery $query): string
+    {
+        return $this->queryComposer->composeLockTable($query);
+    }
+
+    public function composeCreateSavepoint(string $savepointName): string
+    {
+        return $this->queryComposer->composeCreateSavepoint($savepointName);
+    }
+
+    public function composeReleaseSavepoint(string $savepointName): string
+    {
+        return $this->queryComposer->composeReleaseSavepoint($savepointName);
+    }
+
+    public function composeRollbackToSavepoint(string $savepointName): string
+    {
+        return $this->queryComposer->composeRollbackToSavepoint($savepointName);
+    }
+}

application/Espo/ORM/QueryComposer/Util.php

@@ -0,0 +1,199 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\QueryComposer;
+
+class Util
+{
+    public static function isComplexExpression(string $string): bool
+    {
+        if (
+           self::isArgumentString($string) ||
+           self::isArgumentNumeric($string) ||
+           self::isArgumentBoolOrNull($string)
+        ) {
+            return true;
+        }
+
+        if (str_contains($string, '.')) {
+            return true;
+        }
+
+        if (str_contains($string, ':')) {
+            return true;
+        }
+
+        if (str_starts_with($string, '#')) {
+            return true;
+        }
+
+        return false;
+    }
+
+    public static function isArgumentString(string $argument): bool
+    {
+        return
+            str_starts_with($argument, '\'') && str_ends_with($argument, '\'')
+            ||
+            str_starts_with($argument, '"') && str_ends_with($argument, '"');
+    }
+
+    public static function isArgumentNumeric(string $argument): bool
+    {
+        return is_numeric($argument);
+    }
+
+    public static function isArgumentBoolOrNull(string $argument): bool
+    {
+        return in_array(strtoupper($argument), ['NULL', 'TRUE', 'FALSE']);
+    }
+
+    /**
+     * @param string $expression
+     * @return string[]
+     */
+    public static function getAllAttributesFromComplexExpression(string $expression): array
+    {
+        return self::getAllAttributesFromComplexExpressionImplementation($expression);
+    }
+
+    /**
+     * @param string[]|null $list
+     * @return string[]
+     */
+    private static function getAllAttributesFromComplexExpressionImplementation(
+        string $expression,
+        ?array &$list = null
+    ): array {
+
+        if (!$list) {
+            $list = [];
+        }
+
+        if (!strpos($expression, ':')) {
+            if (
+                !self::isArgumentString($expression) &&
+                !self::isArgumentNumeric($expression) &&
+                !self::isArgumentBoolOrNull($expression) &&
+                !str_contains($expression, '#')
+            ) {
+                $list[] = $expression;
+            }
+
+            return $list;
+        }
+
+        $delimiterPosition = strpos($expression, ':');
+        $arguments = substr($expression, $delimiterPosition + 1);
+
+        if (str_starts_with($arguments, '(') && str_ends_with($arguments, ')')) {
+            $arguments = substr($arguments, 1, -1);
+        }
+
+        $argumentList = self::parseArgumentListFromFunctionContent($arguments);
+
+        foreach ($argumentList as $argument) {
+            self::getAllAttributesFromComplexExpressionImplementation($argument, $list);
+        }
+
+        return $list ?? [];
+    }
+
+    /**
+     * @return string[]
+     */
+    static public function parseArgumentListFromFunctionContent(string $functionContent): array
+    {
+        $functionContent = trim($functionContent);
+
+        $isString = false;
+        $isSingleQuote = false;
+
+        if ($functionContent === '') {
+            return [];
+        }
+
+        $commaIndexList = [];
+        $braceCounter = 0;
+
+        for ($i = 0; $i < strlen($functionContent); $i++) {
+            if ($functionContent[$i] === "'" && ($i === 0 || $functionContent[$i - 1] !== "\\")) {
+                if (!$isString) {
+                    $isString = true;
+                    $isSingleQuote = true;
+                } else {
+                    if ($isSingleQuote) {
+                        $isString = false;
+                    }
+                }
+            } else if ($functionContent[$i] === "\"" && ($i === 0 || $functionContent[$i - 1] !== "\\")) {
+                if (!$isString) {
+                    $isString = true;
+                    $isSingleQuote = false;
+                } else {
+                    if (!$isSingleQuote) {
+                        $isString = false;
+                    }
+                }
+            }
+
+            if (!$isString) {
+                if ($functionContent[$i] === '(') {
+                    $braceCounter++;
+                } else if ($functionContent[$i] === ')') {
+                    $braceCounter--;
+                }
+            }
+
+            if ($braceCounter === 0 && !$isString && $functionContent[$i] === ',') {
+                $commaIndexList[] = $i;
+            }
+        }
+
+        $commaIndexList[] = strlen($functionContent);
+
+        $argumentList = [];
+
+        for ($i = 0; $i < count($commaIndexList); $i++) {
+            if ($i > 0) {
+                $previousCommaIndex = $commaIndexList[$i - 1] + 1;
+            } else {
+                $previousCommaIndex = 0;
+            }
+
+            $argument = trim(
+                substr($functionContent, $previousCommaIndex, $commaIndexList[$i] - $previousCommaIndex)
+            );
+
+            $argumentList[] = $argument;
+        }
+
+        return $argumentList;
+    }
+}

application/Espo/ORM/Relation/EmptyRelations.php

@@ -0,0 +1,104 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Relation;
+
+use Espo\ORM\Entity;
+use Espo\ORM\EntityCollection;
+use LogicException;
+use RuntimeException as RuntimeExceptionAlias;
+
+class EmptyRelations implements Relations
+{
+    /** @var array<string, Entity|null> */
+    private array $setData = [];
+
+    public function __construct() {}
+
+    public function resetAll(): void
+    {
+        $this->setData = [];
+    }
+
+    public function reset(string $relation): void
+    {
+        unset($this->setData[$relation]);
+    }
+
+    /**
+     * @param Entity|null $related
+     */
+    public function set(string $relation, Entity|null $related): void
+    {
+        $this->setData[$relation] = $related;
+    }
+
+    public function isSet(string $relation): bool
+    {
+        return array_key_exists($relation, $this->setData);
+    }
+
+    /**
+     * @return Entity|null
+     */
+    public function getSet(string $relation): Entity|null
+    {
+        if (!array_key_exists($relation, $this->setData)) {
+            throw new RuntimeExceptionAlias("Relation '$relation' is not set.");
+        }
+
+        return $this->setData[$relation];
+    }
+
+    public function getOne(string $relation): ?Entity
+    {
+        $entity = $this->setData[$relation] ?? null;
+
+        if ($entity instanceof EntityCollection) {
+            throw new LogicException("Not an entity.");
+        }
+
+        return $entity;
+    }
+
+    /***
+     * @return EntityCollection<Entity>
+     */
+    public function getMany(string $relation): EntityCollection
+    {
+        $collection = $this->setData[$relation] ?? new EntityCollection();
+
+        if (!$collection instanceof EntityCollection) {
+            throw new LogicException("Not a collection.");
+        }
+
+        /** @var EntityCollection<Entity> */
+        return $collection;
+    }
+}

application/Espo/ORM/Relation/RDBRelations.php

@@ -0,0 +1,409 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Relation;
+
+use Espo\ORM\BaseEntity;
+use Espo\ORM\Defs\Defs;
+use Espo\ORM\Defs\Params\RelationParam;
+use Espo\ORM\Defs\RelationDefs;
+use Espo\ORM\Entity;
+use Espo\ORM\EntityCollection;
+use Espo\ORM\EntityManager;
+use Espo\ORM\Mapper\RDBMapper;
+use Espo\ORM\Name\Attribute;
+use Espo\ORM\Query\Part\Order;
+use Espo\ORM\Repository\RDBRelationSelectBuilder;
+use Espo\ORM\Type\RelationType;
+use LogicException;
+use RuntimeException;
+use WeakReference;
+
+/**
+ * @internal
+ */
+class RDBRelations implements Relations
+{
+    /** @var array<string, Entity|EntityCollection<Entity>|null> */
+    private array $data = [];
+    /** @var array<string, Entity|null> */
+    private array $setData = [];
+
+    /** @var WeakReference<Entity>|null  */
+    private ?WeakReference $entity = null;
+
+    /** @var string[] */
+    private array $manyTypeList = [
+        RelationType::MANY_MANY,
+        RelationType::HAS_MANY,
+        RelationType::HAS_CHILDREN,
+    ];
+
+    private Defs $defs;
+
+    public function __construct(
+        private EntityManager $entityManager,
+    ) {
+        $this->defs = $this->entityManager->getDefs();
+    }
+
+    public function getEntity(): Entity
+    {
+        if (!$this->entity) {
+            throw new LogicException("Entity not set.");
+        }
+
+        return $this->entity->get() ?? throw new LogicException("Entity was destroyed.");
+    }
+
+    public function setEntity(Entity $entity): void
+    {
+        if ($this->entity) {
+            throw new LogicException("Entity is already set.");
+        }
+
+        $this->entity = WeakReference::create($entity);
+    }
+
+    public function reset(string $relation): void
+    {
+        unset($this->data[$relation]);
+        unset($this->setData[$relation]);
+    }
+
+    public function resetAll(): void
+    {
+        $this->data = [];
+        $this->setData = [];
+    }
+
+    public function isSet(string $relation): bool
+    {
+        return array_key_exists($relation, $this->setData);
+    }
+
+    /**
+     * @return Entity|null
+     */
+    public function getSet(string $relation): Entity|null
+    {
+        if (!array_key_exists($relation, $this->setData)) {
+            throw new RuntimeException("Relation '$relation' is not set.");
+        }
+
+        return $this->setData[$relation];
+    }
+
+    /**
+     * @param Entity|null $related
+     */
+    public function set(string $relation, Entity|null $related): void
+    {
+        if (!$this->entity) {
+            throw new LogicException("No entity set.");
+        }
+
+        $type = $this->getRelationType($relation);
+
+        if (!$type) {
+            throw new LogicException("Relation '$relation' does not exist.");
+        }
+
+        if (
+            !in_array($type, [
+                RelationType::BELONGS_TO,
+                RelationType::BELONGS_TO_PARENT,
+                RelationType::HAS_ONE,
+            ])
+        ) {
+            throw new LogicException("Relation type '$type' is not supported for setting.");
+        }
+
+        if ($related) {
+            $nameAttribute = $this->entityManager
+                ->getDefs()
+                ->getEntity($this->getEntity()->getEntityType())
+                ->getRelation($relation)
+                ->getParam('nameAttribute') ?? 'name';
+
+            $valueMap = [
+                $relation . 'Id' => $related->getId(),
+                $relation . 'Name' => $related->get($nameAttribute),
+            ];
+
+            if ($type === RelationType::BELONGS_TO_PARENT) {
+                $valueMap[$relation . 'Type'] = $related->getEntityType();
+            }
+        } else {
+            $valueMap = [
+                $relation . 'Id' => null,
+                $relation . 'Name' => null,
+            ];
+
+            if ($type === RelationType::BELONGS_TO_PARENT) {
+                $valueMap[$relation . 'Type'] = null;
+            }
+        }
+
+        $this->getEntity()->setMultiple($valueMap);
+
+        $this->setData[$relation] = $related;
+    }
+
+    public function getOne(string $relation): ?Entity
+    {
+        $entity = $this->get($relation);
+
+        if ($entity instanceof EntityCollection) {
+            throw new LogicException("Not an entity. Use `getMany` instead.");
+        }
+
+        return $entity;
+    }
+
+    /**
+     * @return EntityCollection<Entity>
+     */
+    public function getMany(string $relation): EntityCollection
+    {
+        $collection = $this->get($relation);
+
+        if (!$collection instanceof EntityCollection) {
+            throw new LogicException("Not a collection. Use `getOne` instead.");
+        }
+
+        /** @var EntityCollection<Entity> */
+        return $collection;
+    }
+
+    /**
+     * @param string $relation
+     * @return Entity|EntityCollection<Entity>|null
+     */
+    private function get(string $relation): Entity|EntityCollection|null
+    {
+        if (array_key_exists($relation, $this->setData)) {
+            return $this->setData[$relation];
+        }
+
+        if (!array_key_exists($relation, $this->data)) {
+            if (!$this->entity) {
+                throw new LogicException("No entity set.");
+            }
+
+            $isMany = in_array($this->getRelationType($relation), $this->manyTypeList);
+
+            $this->data[$relation] = $isMany ?
+                $this->findMany($relation) :
+                $this->findOne($relation);
+        }
+
+        $object = $this->data[$relation];
+
+        if ($object instanceof EntityCollection) {
+            /** @var EntityCollection<Entity> $object */
+            $object = new EntityCollection(iterator_to_array($object));
+        }
+
+        return $object;
+    }
+
+    private function findOne(string $relation): ?Entity
+    {
+        if (!$this->entity) {
+            throw new LogicException();
+        }
+
+        if (!$this->getEntity()->hasId() && $this->getRelationType($relation) === RelationType::HAS_ONE) {
+            return null;
+        }
+
+        $foreignEntity = $this->getPartiallyLoadedForeignEntity($relation);
+
+        if ($foreignEntity === false) {
+            // Parent type does not exist. Not throwing an error deliberately.
+            return null;
+        }
+
+        if ($foreignEntity) {
+            return $foreignEntity;
+        }
+
+        $mapper = $this->entityManager->getMapper();
+
+        /** @noinspection PhpConditionAlreadyCheckedInspection */
+        if (!$mapper instanceof RDBMapper) {
+            throw new RuntimeException("Non RDB mapper.");
+        }
+
+        // We use the Mapper as RDBRelation requires an entity with ID.
+
+        $entity = $mapper->selectRelated($this->getEntity(), $relation);
+
+        if (!$entity) {
+            return null;
+        }
+
+        if (!$entity instanceof Entity) {
+            throw new LogicException("Bad mapper return.");
+        }
+
+        return $entity;
+    }
+
+    /**
+     * @return EntityCollection<Entity>
+     */
+    private function findMany(string $relation): EntityCollection
+    {
+        if (!$this->entity) {
+            throw new LogicException();
+        }
+
+        if (!$this->getEntity()->hasId()) {
+            /** @var EntityCollection<Entity> */
+            return new EntityCollection();
+        }
+
+        $relationDefs = $this->defs
+            ->getEntity($this->getEntity()->getEntityType())
+            ->getRelation($relation);
+
+        $builder = $this->entityManager
+            ->getRelation($this->getEntity(), $relation)
+            ->createBuilder();
+
+        $this->applyOrder($relationDefs, $builder);
+
+        $collection = $builder->find();
+
+        if (!$collection instanceof EntityCollection) {
+            $collection = new EntityCollection(iterator_to_array($collection));
+        }
+
+        /** @var EntityCollection<Entity> */
+        return $collection;
+    }
+
+    private function getRelationType(string $relation): ?string
+    {
+        if (!$this->entity) {
+            throw new LogicException();
+        }
+
+        return $this->defs
+            ->getEntity($this->getEntity()->getEntityType())
+            ->tryGetRelation($relation)
+            ?->getType();
+    }
+
+    private function getPartiallyLoadedForeignEntity(string $relation): BaseEntity|false|null
+    {
+        if (!$this->entity) {
+            throw new LogicException();
+        }
+
+        $defs = $this->defs
+            ->getEntity($this->getEntity()->getEntityType())
+            ->getRelation($relation);
+
+        if (!$defs->getParam(RelationParam::DEFERRED_LOAD)) {
+            return null;
+        }
+
+        $relationType = $defs->getType();
+
+        $id = null;
+        $foreignEntityType = null;
+
+        if ($relationType === RelationType::BELONGS_TO) {
+            $foreignEntityType = $defs->getForeignEntityType();
+            $nameAttribute = $relation . 'Name';
+            $id = $this->getEntity()->get($relation . 'Id');
+            $name = $this->getEntity()->get($nameAttribute);
+
+            if (
+                $id &&
+                $name === null &&
+                $this->getEntity()->hasAttribute($nameAttribute) &&
+                $this->getEntity()->has($nameAttribute)
+            ) {
+                $hasDeleted = $this->defs
+                    ->getEntity($foreignEntityType)
+                    ->hasAttribute(Attribute::DELETED);
+
+                if ($hasDeleted) {
+                    // Could be either soft-deleted or have name set to null.
+                    // We resort to not using a partially loaded entity.
+                    return null;
+                }
+            }
+        } else if ($relationType === RelationType::BELONGS_TO_PARENT) {
+            $foreignEntityType = $this->getEntity()->get($relation . 'Type');
+            $id = $this->getEntity()->get($relation . 'Id');
+
+            if (!$this->entityManager->hasRepository($foreignEntityType)) {
+                return false;
+            }
+        }
+
+        if (!$foreignEntityType || !$id) {
+            return null;
+        }
+
+        $foreignEntity = $this->entityManager->getNewEntity($foreignEntityType);
+
+        if (!$foreignEntity instanceof BaseEntity) {
+            return null;
+        }
+
+        $foreignEntity->set(Attribute::ID, $id);
+        $foreignEntity->setAsFetched();
+        $foreignEntity->setAsPartiallyLoaded();
+
+        return $foreignEntity;
+    }
+
+    private function applyOrder(RelationDefs $relationDefs, RDBRelationSelectBuilder $builder): void
+    {
+        $orderBy = $relationDefs->getParam(RelationParam::ORDER_BY);
+
+        if (!$orderBy) {
+            return;
+        }
+
+        $order = $relationDefs->getParam(RelationParam::ORDER);
+
+        if ($order !== null) {
+            $order = strtoupper($order) === Order::DESC ? Order::DESC : Order::ASC;
+        }
+
+        $builder->order($orderBy, $order);
+    }
+}

application/Espo/ORM/Relation/Relations.php

@@ -0,0 +1,78 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Relation;
+
+use Espo\ORM\Entity;
+use Espo\ORM\EntityCollection;
+
+/**
+ * @internal Not ready for production.
+ */
+interface Relations
+{
+    /**
+     * Reset a specific relation.
+     */
+    public function reset(string $relation): void;
+
+    /**
+     * Reset all.
+     */
+    public function resetAll(): void;
+
+    /**
+     * @param Entity|null $related
+     */
+    public function set(string $relation, Entity|null $related): void;
+
+    /**
+     * Is a relation set (updated).
+     */
+    public function isSet(string $relation): bool;
+
+    /**
+     * Get set (updated) record or records.
+     *
+     * @return Entity|null
+     */
+    public function getSet(string $relation): Entity|null;
+
+    /**
+     * Get one related record. For has-one, belongs-to.
+     */
+    public function getOne(string $relation): ?Entity;
+
+    /**
+     * Get a collection of related records. For has-many, many-many, has-children.
+     *
+     * @return EntityCollection<Entity>
+     */
+    public function getMany(string $relation): EntityCollection;
+}

application/Espo/ORM/Relation/RelationsMap.php

@@ -0,0 +1,54 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Relation;
+
+use Espo\ORM\Entity;
+use WeakMap;
+
+class RelationsMap
+{
+    /** @var WeakMap<Entity, Relations> */
+    private WeakMap $map;
+
+    public function __construct()
+    {
+        $this->map = new WeakMap();
+    }
+
+    public function get(Entity $entity): ?Relations
+    {
+        return $this->map[$entity] ?? null;
+    }
+
+    public function set(Entity $entity, Relations $relations): void
+    {
+        $this->map[$entity] = $relations;
+    }
+}

application/Espo/ORM/Repository/Deprecation/RDBRepositoryDeprecationTrait.php

@@ -0,0 +1,54 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Repository\Deprecation;
+
+use Espo\ORM\Entity;
+
+/**
+ * @internal
+ * @template TEntity of Entity
+ */
+trait RDBRepositoryDeprecationTrait
+{
+    /**
+     * Get an entity. If ID is NULL, a new entity is returned.
+     *
+     * @deprecated Use `getById` and `getNew`.
+     * @todo Remove in v10.0.
+     */
+    public function get(?string $id = null): ?Entity
+    {
+        if (is_null($id)) {
+            return $this->getNew();
+        }
+
+        return $this->getById($id);
+    }
+}

application/Espo/ORM/Repository/EmptyHookMediator.php

@@ -0,0 +1,66 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM – Open Source CRM application.
+ * Copyright (C) 2014-2025 EspoCRM, Inc.
+ * Website: https://www.espocrm.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU Affero General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU Affero General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\ORM\Repository;
+
+use Espo\ORM\Entity;
+use Espo\ORM\Query\Select;
+
+class EmptyHookMediator implements HookMediator
+{
+    public function beforeSave(Entity $entity, array $options): void
+    {}
+
+    public function afterSave(Entity $entity, array $options): void
+    {}
+
+    public function beforeRemove(Entity $entity, array $options): void
+    {}
+
+    public function afterRemove(Entity $entity, array $options): void
+    {}
+
+    public function beforeRelate(Entity $entity, string $relationName, Entity $foreignEntity, ?array $columnData, array $options): void
+    {}
+
+    public function afterRelate(Entity $entity, string $relationName, Entity $foreignEntity, ?array $columnData, array $options): void
+    {}
+
+    public function beforeUnrelate(Entity $entity, string $relationName, Entity $foreignEntity, array $options): void
+    {}
+
+    public function afterUnrelate(Entity $entity, string $relationName, Entity $foreignEntity, array $options): void
+    {}
+
+    public function beforeMassRelate(Entity $entity, string $relationName, Select $query, array $options): void
+    {}
+
+    public function afterMassRelate(Entity $entity, string $relationName, Select $query, array $options): void
+    {}
+}