diff --git a/application/Espo/Core/ORM/Entity.php b/application/Espo/Core/ORM/Entity.php
index 7ffa140c10..2281efd05f 100644
--- a/application/Espo/Core/ORM/Entity.php
+++ b/application/Espo/Core/ORM/Entity.php
@@ -56,7 +56,7 @@ class Entity extends BaseEntity
             $this->hasRelation($field);
     }
 
-    public function loadParentNameField(string $field)
+    public function loadParentNameField(string $field) : void
     {
         if (!$this->hasAttribute($field. 'Id') || !$this->hasAttribute($field . 'Type')) {
             throw new LogicException("There's no link-parent field '{$field}'.");
@@ -81,12 +81,16 @@ class Entity extends BaseEntity
 
             if ($foreignEntity) {
                 $this->set($field . 'Name', $foreignEntity->get('name'));
-            } else {
-                $this->set($field . 'Name', null);
+
+                return;
             }
-        } else {
+
             $this->set($field . 'Name', null);
+
+            return;
         }
+
+        $this->set($field . 'Name', null);
     }
 
     protected function getRelationOrderParams(string $link) : ?array
@@ -141,7 +145,7 @@ class Entity extends BaseEntity
         ];
     }
 
-    public function loadLinkMultipleField(string $field, $columns = null)
+    public function loadLinkMultipleField(string $field, $columns = null) : void
     {
         if (!$this->hasRelation($field) || !$this->hasAttribute($field . 'Ids')) {
             return;
@@ -158,7 +162,7 @@ class Entity extends BaseEntity
         }
 
         if (!empty($columns)) {
-            foreach ($columns as $key => $item) {
+            foreach ($columns as $item) {
                 $select[] = $item;
             }
         }
@@ -186,7 +190,9 @@ class Entity extends BaseEntity
 
         foreach ($collection as $e) {
             $id = $e->id;
+
             $ids[] = $id;
+
             $names->$id = $e->get('name');
 
             if ($hasType) {
@@ -221,7 +227,7 @@ class Entity extends BaseEntity
         }
     }
 
-    public function loadLinkField(string $field)
+    public function loadLinkField(string $field) : void
     {
         if (!$this->hasRelation($field) || !$this->hasAttribute($field . 'Id')) {
             throw new LogicException("There's no link field '{$field}'.");
@@ -254,9 +260,13 @@ class Entity extends BaseEntity
         }
 
         $this->set($idAttribute, $entityId);
+
         $this->set($field . 'Name', $entityName);
     }
 
+    /**
+     * @return ?mixed
+     */
     public function getLinkMultipleName(string $field, string $id)
     {
         $namesAttribute = $field . 'Names';
@@ -267,18 +277,14 @@ class Entity extends BaseEntity
 
         $names = $this->get($namesAttribute);
 
-        if ($names instanceof StdClass) {
-            if (isset($names->$id)) {
-                if (isset($names->$id)) {
-                    return $names->$id;
-                }
-            }
+        if ($names instanceof StdClass && isset($names->$id) && isset($names->$id)) {
+            return $names->$id;
         }
 
         return null;
     }
 
-    public function setLinkMultipleName(string $field, string $id, ?string $value)
+    public function setLinkMultipleName(string $field, string $id, ?string $value) : void
     {
         $namesAttribute = $field . 'Names';
 
@@ -293,9 +299,13 @@ class Entity extends BaseEntity
         }
 
         $object->$id = $value;
+
         $this->set($namesAttribute, $object);
     }
 
+    /**
+     * @return ?mixed
+     */
     public function getLinkMultipleColumn(string $field, string $column, string $id)
     {
         $columnsAttribute = $field . 'Columns';
@@ -306,18 +316,14 @@ class Entity extends BaseEntity
 
         $columns = $this->get($columnsAttribute);
 
-        if ($columns instanceof StdClass) {
-            if (isset($columns->$id)) {
-                if (isset($columns->$id->$column)) {
-                    return $columns->$id->$column;
-                }
-            }
+        if ($columns instanceof StdClass && isset($columns->$id) && isset($columns->$id->$column)) {
+            return $columns->$id->$column;
         }
 
         return null;
     }
 
-    public function setLinkMultipleColumn(string $field, string $column, string $id, $value)
+    public function setLinkMultipleColumn(string $field, string $column, string $id, $value) : void
     {
         $columnsAttribute = $field . 'Columns';
 
@@ -344,14 +350,14 @@ class Entity extends BaseEntity
         $this->set($columnsAttribute, $object);
     }
 
-    public function setLinkMultipleIdList(string $field, array $idList)
+    public function setLinkMultipleIdList(string $field, array $idList) : void
     {
         $idsAttribute = $field . 'Ids';
 
         $this->set($idsAttribute, $idList);
     }
 
-    public function addLinkMultipleId(string $field, string $id)
+    public function addLinkMultipleId(string $field, string $id) : void
     {
         $idsAttribute = $field . 'Ids';
 
@@ -379,7 +385,7 @@ class Entity extends BaseEntity
         }
     }
 
-    public function removeLinkMultipleId(string $field, string $id)
+    public function removeLinkMultipleId(string $field, string $id) : void
     {
         if ($this->hasLinkMultipleId($field, $id)) {
             $list = $this->getLinkMultipleIdList($field);
@@ -421,7 +427,9 @@ class Entity extends BaseEntity
     {
         $idsAttribute = $field . 'Ids';
 
-        if (!$this->hasAttribute($idsAttribute)) return false;
+        if (!$this->hasAttribute($idsAttribute)) {
+            return false;
+        }
 
         if (!$this->has($idsAttribute)) {
             if (!$this->isNew()) {
diff --git a/application/Espo/Entities/Integration.php b/application/Espo/Entities/Integration.php
index f24bfd1384..c2f1bb546e 100644
--- a/application/Espo/Entities/Integration.php
+++ b/application/Espo/Entities/Integration.php
@@ -122,6 +122,10 @@ class Integration extends \Espo\Core\ORM\Entity
         return parent::isAttributeChanged($name);
     }
 
+    /**
+     * @deprecated
+     * @todo Make protected.
+     */
     public function populateFromArray(array $array, bool $onlyAccessible = true, bool $reset = false) : void
     {
         if ($reset) {
@@ -141,29 +145,43 @@ class Integration extends \Espo\Core\ORM\Entity
                 if (!is_null($value)) {
                     switch ($defs['type']) {
                         case self::VARCHAR:
+
                             break;
+
                         case self::BOOL:
                             $value = ($value === 'true' || $value === '1' || $value === true);
+
                             break;
+
                         case self::INT:
                             $value = intval($value);
+
                             break;
+
                         case self::FLOAT:
                             $value = floatval($value);
+
                             break;
+
                         case self::JSON_ARRAY:
                             $value = is_string($value) ? json_decode($value) : $value;
+
                             if (!is_array($value)) {
                                 $value = null;
                             }
                             break;
+
                         case self::JSON_OBJECT:
                             $value = is_string($value) ? json_decode($value) : $value;
-                            if (!($value instanceof \StdClass) && !is_array($value)) {
+
+                            if (!($value instanceof StdClass) && !is_array($value)) {
                                 $value = null;
                             }
+
                             break;
+
                         default:
+
                             break;
                     }
                 }
diff --git a/application/Espo/ORM/BaseEntity.php b/application/Espo/ORM/BaseEntity.php
index 980629fe70..f64b2ac41b 100644
--- a/application/Espo/ORM/BaseEntity.php
+++ b/application/Espo/ORM/BaseEntity.php
@@ -29,21 +29,24 @@
 
 namespace Espo\ORM;
 
-use StdClass;
-
 use const E_USER_DEPRECATED;
 
+use StdClass;
 use InvalidArgumentException;
 
 class BaseEntity implements Entity
 {
     public $id = null;
 
+    protected $entityType;
+
     private $isNew = false;
 
     private $isSaved = false;
 
-    protected $entityType;
+    protected $isFetched = false;
+
+    protected $isBeingSaved = false;
 
     /**
      * @todo Make protected. Rename to `attributes`.
@@ -54,21 +57,20 @@ class BaseEntity implements Entity
     protected $relations = [];
 
     /**
-     * @var array Field-Value pairs.
+     * A field-value map.
      */
     protected $valuesContainer = [];
 
     /**
-     * @var array Field-Value pairs of initial values (fetched from DB).
+     * A field-value map of values fetched from DB (before changed).
      */
     protected $fetchedValuesContainer = [];
 
+    /**
+     * @var ?EntityManager
+     */
     protected $entityManager;
 
-    protected $isFetched = false;
-
-    protected $isBeingSaved = false;
-
     public function __construct(string $entityType, array $defs = [], ?EntityManager $entityManager = null)
     {
         $this->entityType = $entityType ?? null;
@@ -79,6 +81,11 @@ class BaseEntity implements Entity
         $this->relations = $defs['relations'] ?? $this->relations;
     }
 
+    public function getId() : ?string
+    {
+        return $this->get('id');
+    }
+
     public function clear(string $name) : void
     {
         unset($this->valuesContainer[$name]);
@@ -125,16 +132,22 @@ class BaseEntity implements Entity
                 $this->id = $value;
             }
 
-            if ($this->hasAttribute($name)) {
-                $method = '_set' . ucfirst($name);
-
-                if (method_exists($this, $method)) {
-                    $this->$method($value);
-                } else {
-                    $this->valuesContainer[$name] = $value;
-                }
+            if (!$this->hasAttribute($name)) {
+                return;
             }
 
+            $method = '_set' . ucfirst($name);
+
+            if (method_exists($this, $method)) {
+                $this->$method($value);
+
+                return;
+            }
+
+            $this->populateFromArray([
+                $name => $value,
+            ]);
+
             return;
         }
 
@@ -148,7 +161,7 @@ class BaseEntity implements Entity
      */
     public function get(string $name, $params = [])
     {
-        if ($name == 'id') {
+        if ($name === 'id') {
             return $this->id;
         }
 
@@ -172,7 +185,8 @@ class BaseEntity implements Entity
         // @todo Remove this.
         if ($this->hasRelation($name) && $this->id && $this->entityManager) {
             trigger_error(
-                "Accessing related records with Entity::get is deprecated. Use \$repository->getRelation(...)->find()",
+                "Accessing related records with Entity::get is deprecated. " .
+                "Use \$repository->getRelation(...)->find()",
                 E_USER_DEPRECATED
             );
 
@@ -203,13 +217,17 @@ class BaseEntity implements Entity
         return false;
     }
 
+    /**
+     * @deprecated
+     * @todo Make protected.
+     */
     public function populateFromArray(array $data, bool $onlyAccessible = true, bool $reset = false) : void
     {
         if ($reset) {
             $this->reset();
         }
 
-        foreach ($this->getAttributes() as $attribute => $defs) {
+        foreach ($this->getAttributeList() as $attribute) {
             if (!array_key_exists($attribute, $data)) {
                 continue;
             }
@@ -226,79 +244,122 @@ class BaseEntity implements Entity
 
             $value = $data[$attribute];
 
-            if (!is_null($value)) {
-                $valueType = $this->getAttributeType($attribute);
-
-                if ($valueType === self::FOREIGN) {
-                    $relation = $this->getAttributeParam($attribute, 'relation');
-                    $foreign = $this->getAttributeParam($attribute, 'foreign');
-
-                    if (is_string($foreign)) {
-                        $foreignEntityType = $this->getRelationParam($relation, 'entity');
-
-                        if ($foreignEntityType && $this->entityManager) {
-                            $valueType = $this->entityManager->getMetadata()->get(
-                                $foreignEntityType, ['fields', $foreign, 'type']
-                            );
-                        }
-                    }
-                }
-
-                switch ($valueType) {
-                    case self::VARCHAR:
-
-                        break;
-
-                    case self::BOOL:
-                        $value = ($value === 'true' || $value === '1' || $value === true);
-
-                        break;
-
-                    case self::INT:
-                        $value = intval($value);
-
-                        break;
-
-                    case self::FLOAT:
-                        $value = floatval($value);
-
-                        break;
-
-                    case self::JSON_ARRAY:
-                        $value = is_string($value) ? json_decode($value) : $value;
-
-                        if (!is_array($value)) {
-                            $value = null;
-                        }
-
-                        break;
-
-                    case self::JSON_OBJECT:
-                        $value = is_string($value) ? json_decode($value) : $value;
-
-                        if (!($value instanceof StdClass) && !is_array($value)) {
-                            $value = null;
-                        }
-
-                        break;
-
-                    default:
-                        break;
-                }
-            }
-
-            $method = '_set' . ucfirst($attribute);
-
-            if (method_exists($this, $method)) {
-                $this->$method($value);
-
-                continue;
-            }
-
-            $this->valuesContainer[$attribute] = $value;
+            $this->populateFromArrayItem($attribute, $value);
         }
     }
 
+    protected function populateFromArrayItem(string $attribute, $value) : void
+    {
+        $preparedValue = $this->preparePopulateFromArrayItemValue($attribute, $value);
+
+        $method = '_set' . ucfirst($attribute);
+
+        if (method_exists($this, $method)) {
+            $this->$method($preparedValue);
+
+            return;
+        }
+
+        $this->valuesContainer[$attribute] = $preparedValue;
+    }
+
+    /**
+     * @return ?mixed
+     */
+    protected function preparePopulateFromArrayItemValue(string $attribute, $value)
+    {
+        if (is_null($value)) {
+            return $value;
+        }
+
+        $attributeType = $this->getAttributeType($attribute);
+
+        if ($attributeType === self::FOREIGN) {
+            $attributeType = $this->getForeignAttributeType($attribute) ?? $attributeType;
+        }
+
+        switch ($attributeType) {
+            case self::VARCHAR:
+                break;
+
+            case self::BOOL:
+                return ($value === true || $value === 'true' || $value === '1');
+
+            case self::INT:
+                return intval($value);
+
+            case self::FLOAT:
+                return floatval($value);
+
+            case self::JSON_ARRAY:
+                $preparedValue = is_string($value) ? json_decode($value) : $value;
+
+                if (!is_array($preparedValue)) {
+                    $value = null;
+                }
+
+                return $preparedValue;
+
+            case self::JSON_OBJECT:
+                $preparedValue = is_string($value) ? json_decode($value) : $value;
+
+                if (!($preparedValue instanceof StdClass) && !is_array($preparedValue)) {
+                    $preparedValue = null;
+                }
+
+                return $preparedValue;
+
+            default:
+                break;
+        }
+
+        return $value;
+    }
+
+    private function getForeignAttributeType(string $attribute) : ?string
+    {
+        if (!$this->entityManager) {
+            return null;
+        }
+
+        $defs = $this->entityManager->getDefs();
+
+        $entityDefs = $defs->getEntity($this->entityType);
+
+        $relation = $entityDefs->getAttribute($attribute)->getParam('relation');
+        $foreign = $entityDefs->getAttribute($attribute)->getParam('foreign');
+
+        if (!$relation) {
+            return null;
+        }
+
+        if (!$foreign) {
+            return null;
+        }
+
+        if (!is_string($foreign)) {
+            return self::VARCHAR;
+        }
+
+        if (!$entityDefs->getRelation($relation)->hasForeignEntityType()) {
+            return null;
+        }
+
+        $entityType = $entityDefs->getRelation($relation)->getForeignEntityType();
+
+        if (!$defs->hasEntity($entityType)) {
+            return null;
+        }
+
+        $foreignEntityDefs = $defs->getEntity($entityType);
+
+        if (!$foreignEntityDefs->hasAttribute($foreign)) {
+            return null;
+        }
+
+        return $foreignEntityDefs->getAttribute($foreign)->getType();
+    }
+
     /**
      * Is an entity new.
      */
diff --git a/application/Espo/ORM/Entity.php b/application/Espo/ORM/Entity.php
index 7379db5388..87bab08eeb 100644
--- a/application/Espo/ORM/Entity.php
+++ b/application/Espo/ORM/Entity.php
@@ -56,6 +56,11 @@ interface Entity
     const BELONGS_TO_PARENT = 'belongsToParent';
     const HAS_CHILDREN = 'hasChildren';
 
+    /**
+     * Get an entity ID.
+     */
+    public function getId() : ?string;
+
     /**
      * Reset all attributes (empty an entity).
      */
diff --git a/tests/unit/Espo/ORM/EntityTest.php b/tests/unit/Espo/ORM/EntityTest.php
index 21ff1fb33c..c8b345914d 100644
--- a/tests/unit/Espo/ORM/EntityTest.php
+++ b/tests/unit/Espo/ORM/EntityTest.php
@@ -30,11 +30,11 @@
 namespace tests\unit\Espo\ORM;
 
 use Espo\ORM\{
-    DB\MysqlMapper,
-    DB\Query\Mysql as Query,
-    EntityFactory,
     Metadata,
     MetadataDataProvider,
+    Defs\Defs,
+    Defs\DefsData,
+    BaseEntity,
 };
 
 use tests\unit\testData\DB\Job;
@@ -57,19 +57,30 @@ class EntityTest extends \PHPUnit\Framework\TestCase
             ->willReturn($ormMetadata);
 
         $this->metadata = new Metadata($metadataDataProvider);
+
+        $defsData = new DefsData($this->metadata);
+
+        $defs = new Defs($defsData);
+
+        $this->entityManager = $this->createMock(EntityManager::class);
+
+        $this->entityManager
+            ->expects($this->any())
+            ->method('getDefs')
+            ->willReturn($defs);
     }
 
     protected function tearDown() : void
     {
     }
 
-    protected function createEntity(string $entityType, string $className)
+    protected function createEntity(string $entityType, ?string $className = null)
     {
-        $em = $this->getMockBuilder(EntityManager::class)->disableOriginalConstructor()->getMock();
-
         $defs = $this->metadata->get($entityType);
 
-        $entity = new $className($entityType, $defs, $em);
+        $classNameToUse = $className ?? BaseEntity::class;
+
+        $entity = new $classNameToUse($entityType, $defs, $this->entityManager);
 
         return $entity;
     }
@@ -236,4 +247,43 @@ class EntityTest extends \PHPUnit\Framework\TestCase
         ]);
         $this->assertTrue($job->isAttributeChanged('object'));
     }
+
+    public function testSetForeign()
+    {
+        $entity = $this->createEntity('Comment');
+
+        $entity->set([
+            'postName' => 'test',
+        ]);
+
+        $this->assertEquals('test', $entity->get('postName'));
+    }
+
+    public function testSetJsonObject()
+    {
+        $entity = $this->createEntity('Test');
+
+        $value = '{"test": "1"}';
+
+        $entity->set([
+            'object' => '{"test": "1"}',
+        ]);
+
+        $this->assertEquals(json_decode($value), $entity->get('object'));
+    }
+
+    public function testSetWrongType()
+    {
+        $entity = $this->createEntity('Test');
+
+        $entity->set([
+            'int' => '1',
+        ]);
+
+        $this->assertEquals(1, $entity->get('int'));
+
+        $entity->set('int', '1');
+
+        $this->assertEquals(1, $entity->get('int'));
+    }
 }