diff --git a/src/CoreBundle/Entity/AccessUrlRelUser.php b/src/CoreBundle/Entity/AccessUrlRelUser.php
index 61bd0ae006..fbb77da84f 100644
--- a/src/CoreBundle/Entity/AccessUrlRelUser.php
+++ b/src/CoreBundle/Entity/AccessUrlRelUser.php
@@ -37,13 +37,13 @@ class AccessUrlRelUser
      * @ORM\ManyToOne(targetEntity="Chamilo\CoreBundle\Entity\User", inversedBy="portals")
      * @ORM\JoinColumn(name="user_id", referencedColumnName="id", onDelete="CASCADE")
      */
-    protected $user;
+    protected User $user;
 
     /**
      * @ORM\ManyToOne(targetEntity="AccessUrl", inversedBy="user", cascade={"persist"})
      * @ORM\JoinColumn(name="access_url_id", referencedColumnName="id")
      */
-    protected $url;
+    protected AccessUrl $url;
 
     /**
      * @return string
diff --git a/src/CoreBundle/Entity/GradebookCategory.php b/src/CoreBundle/Entity/GradebookCategory.php
index 2185b92f95..0fecafd608 100644
--- a/src/CoreBundle/Entity/GradebookCategory.php
+++ b/src/CoreBundle/Entity/GradebookCategory.php
@@ -468,11 +468,6 @@ class GradebookCategory
         return $this->parent;
     }
 
-    /**
-     * @param GradebookCategory|null $parent
-     *
-     * @return GradebookCategory
-     */
     public function setParent(?GradebookCategory $parent): self
     {
         $this->parent = $parent;
diff --git a/src/CoreBundle/Entity/GradebookResult.php b/src/CoreBundle/Entity/GradebookResult.php
index e76ebafc39..eb1f00ac35 100644
--- a/src/CoreBundle/Entity/GradebookResult.php
+++ b/src/CoreBundle/Entity/GradebookResult.php
@@ -37,6 +37,12 @@ class GradebookResult
      */
     protected GradebookEvaluation $evaluation;
 
+    /**
+     * @ORM\ManyToOne(targetEntity="Chamilo\CoreBundle\Entity\User", inversedBy="gradeBookResults")
+     * @ORM\JoinColumn(name="user_id", referencedColumnName="id", onDelete="CASCADE")
+     */
+    protected User $user;
+
     /**
      * @var float
      *
@@ -52,12 +58,6 @@ class GradebookResult
      */
     protected $createdAt;
 
-    /**
-     * @ORM\ManyToOne(targetEntity="Chamilo\CoreBundle\Entity\User", inversedBy="gradeBookResults")
-     * @ORM\JoinColumn(name="user_id", referencedColumnName="id", onDelete="CASCADE")
-     */
-    protected User $user;
-
     /**
      * Set evaluationId.
      *
diff --git a/src/CoreBundle/Migrations/AbstractMigrationChamilo.php b/src/CoreBundle/Migrations/AbstractMigrationChamilo.php
index 65f9afefd4..8f880712da 100644
--- a/src/CoreBundle/Migrations/AbstractMigrationChamilo.php
+++ b/src/CoreBundle/Migrations/AbstractMigrationChamilo.php
@@ -215,8 +215,15 @@ abstract class AbstractMigrationChamilo extends AbstractMigration implements Con
         }
     }
 
-    public function fixItemProperty($tool, $repo, $course, $admin, ResourceInterface $resource, $parent)
-    {
+    public function fixItemProperty(
+        $tool,
+        $repo,
+        $course,
+        $admin,
+        ResourceInterface $resource,
+        $parent,
+        array $items = []
+    ) {
         $container = $this->getContainer();
         $doctrine = $container->get('doctrine');
         $em = $doctrine->getManager();
@@ -226,12 +233,14 @@ abstract class AbstractMigrationChamilo extends AbstractMigration implements Con
         $courseId = $course->getId();
         $id = $resource->getResourceIdentifier();
 
-        $sql = "SELECT * FROM c_item_property
-                WHERE tool = '$tool' AND c_id = $courseId AND ref = $id";
-        $result = $connection->executeQuery($sql);
-        $items = $result->fetchAllAssociative();
+        if (empty($items)) {
+            $sql = "SELECT * FROM c_item_property
+                    WHERE tool = '$tool' AND c_id = $courseId AND ref = $id";
+            $result = $connection->executeQuery($sql);
+            $items = $result->fetchAllAssociative();
+        }
 
-        // For some reason this document doesnt have a c_item_property value.
+        // For some reason the resource doesnt have a c_item_property value.
         if (empty($items)) {
             return false;
         }
@@ -250,9 +259,9 @@ abstract class AbstractMigrationChamilo extends AbstractMigration implements Con
         $sessionList = [];
         foreach ($items as $item) {
             $visibility = $item['visibility'];
-            $sessionId = $item['session_id'];
             $userId = $item['insert_user_id'];
-            $groupId = $item['to_group_id'];
+            $sessionId = $item['session_id'] ?? 0;
+            $groupId = $item['to_group_id'] ?? 0;
 
             $newVisibility = ResourceLink::VISIBILITY_PENDING;
             switch ($visibility) {
diff --git a/src/CoreBundle/Migrations/Schema/V200/Version20.php b/src/CoreBundle/Migrations/Schema/V200/Version20.php
index 7f49b5b6b8..ec73df88e9 100644
--- a/src/CoreBundle/Migrations/Schema/V200/Version20.php
+++ b/src/CoreBundle/Migrations/Schema/V200/Version20.php
@@ -112,6 +112,11 @@ class Version20 extends AbstractMigrationChamilo
         if ($table->hasColumn('course')) {
             $this->addSql('ALTER TABLE personal_agenda DROP course');
         }
+
+        if ($table->hasIndex('category_code')) {
+            $this->addSql('DROP INDEX category_code ON course');
+        }
+
         if (false === $table->hasForeignKey('FK_D86124608D93D649')) {
             $this->addSql('ALTER TABLE personal_agenda ADD CONSTRAINT FK_D86124608D93D649 FOREIGN KEY (user) REFERENCES user (id) ON DELETE CASCADE');
         }
diff --git a/src/CoreBundle/Migrations/Schema/V200/Version20170625122900.php b/src/CoreBundle/Migrations/Schema/V200/Version20170625122900.php
index 97804f5fdc..cc588d0e2b 100644
--- a/src/CoreBundle/Migrations/Schema/V200/Version20170625122900.php
+++ b/src/CoreBundle/Migrations/Schema/V200/Version20170625122900.php
@@ -43,6 +43,10 @@ class Version20170625122900 extends AbstractMigrationChamilo
             $this->addSql('CREATE INDEX idx_cdoc_type ON c_document (filetype)');
         }
 
+        if (false === $table->hasIndex('course')) {
+            $this->addSql('DROP INDEX course ON c_document');
+        }
+
         //$this->addSql('ALTER TABLE c_document CHANGE path path VARCHAR(255) DEFAULT NULL;');
         $table = $schema->getTable('c_announcement');
         if (false === $table->hasColumn('resource_node_id')) {
diff --git a/src/CoreBundle/Migrations/Schema/V200/Version20170625143000.php b/src/CoreBundle/Migrations/Schema/V200/Version20170625143000.php
index 6a7553a1e8..6a7e4fe626 100644
--- a/src/CoreBundle/Migrations/Schema/V200/Version20170625143000.php
+++ b/src/CoreBundle/Migrations/Schema/V200/Version20170625143000.php
@@ -88,9 +88,10 @@ class Version20170625143000 extends AbstractMigrationChamilo
         $table = $schema->getTable('c_thematic_plan');
         $this->addSql('ALTER TABLE c_thematic_plan CHANGE thematic_id thematic_id INT DEFAULT NULL');
 
-        if (false === $table->hasIndex('course')) {
+        if ($table->hasIndex('course')) {
             $this->addSql('DROP INDEX course ON c_thematic_plan');
         }
+
         if ($table->hasColumn('c_id')) {
             //$this->addSql('ALTER TABLE c_thematic_plan DROP c_id;');
         }
@@ -153,6 +154,15 @@ class Version20170625143000 extends AbstractMigrationChamilo
         }
 
         $table = $schema->getTable('c_glossary');
+
+        if ($table->hasIndex('course')) {
+            $this->addSql('DROP INDEX course ON c_glossary');
+        }
+
+        if ($table->hasIndex('session_id')) {
+            $this->addSql('DROP INDEX session_id ON c_glossary');
+        }
+
         if (false === $table->hasColumn('resource_node_id')) {
             $this->addSql('ALTER TABLE c_glossary ADD resource_node_id INT DEFAULT NULL');
             $this->addSql(
@@ -224,7 +234,21 @@ class Version20170625143000 extends AbstractMigrationChamilo
             $this->addSql('CREATE UNIQUE INDEX UNIQ_A06225811BAD783F ON c_calendar_event (resource_node_id)');
         }
 
+        if ($table->hasIndex('course')) {
+            $this->addSql('DROP INDEX course ON c_calendar_event');
+        }
+
+        if ($table->hasIndex('session_id')) {
+            $this->addSql('DROP INDEX session_id ON c_calendar_event');
+        }
+
+
         $table = $schema->getTable('c_calendar_event_attachment');
+
+        if ($table->hasIndex('course')) {
+            $this->addSql('DROP INDEX course ON c_calendar_event_attachment');
+        }
+
         if (false === $table->hasColumn('resource_node_id')) {
             $this->addSql('ALTER TABLE c_calendar_event_attachment ADD resource_node_id INT DEFAULT NULL');
             $this->addSql(
@@ -250,12 +274,20 @@ class Version20170625143000 extends AbstractMigrationChamilo
             $this->addSql('CREATE INDEX IDX_86FD1CA87300D633 ON c_calendar_event_repeat (cal_id)');
         }
 
-        $this->addSql('ALTER TABLE c_calendar_event_repeat_not CHANGE cal_id cal_id INT DEFAULT NULL');
+        $table = $schema->getTable('c_calendar_event_repeat_not');
+
+        if ($table->hasIndex('course')) {
+            $this->addSql('DROP INDEX course ON c_calendar_event_repeat_not;');
+        }
+
         if (false === $table->hasForeignKey('FK_7D4436947300D633')) {
             $this->addSql(
                 'ALTER TABLE c_calendar_event_repeat_not ADD CONSTRAINT FK_7D4436947300D633 FOREIGN KEY (cal_id) REFERENCES c_calendar_event (iid)'
             );
         }
+
+        $this->addSql('ALTER TABLE c_calendar_event_repeat_not CHANGE cal_id cal_id INT DEFAULT NULL');
+
         if (false === $table->hasIndex('IDX_7D4436947300D633')) {
             $this->addSql('CREATE INDEX IDX_7D4436947300D633 ON c_calendar_event_repeat_not (cal_id)');
         }
diff --git a/src/CoreBundle/Migrations/Schema/V200/Version20170625153000.php b/src/CoreBundle/Migrations/Schema/V200/Version20170625153000.php
index ea3c9564c7..92967b56a9 100644
--- a/src/CoreBundle/Migrations/Schema/V200/Version20170625153000.php
+++ b/src/CoreBundle/Migrations/Schema/V200/Version20170625153000.php
@@ -51,7 +51,20 @@ class Version20170625153000 extends AbstractMigrationChamilo
             $this->addSql('CREATE UNIQUE INDEX UNIQ_47A9C991BAD783F ON c_forum_forum (resource_node_id)');
         }
 
-        $this->addSql('ALTER TABLE c_forum_forum DROP FOREIGN KEY FK_47A9C9921BF9426');
+        if ($table->hasIndex('FK_47A9C9968DFD1EF')) {
+            $this->addSql('ALTER TABLE c_forum_forum DROP INDEX FK_47A9C9968DFD1EF');
+        }
+
+        $this->addSql('ALTER TABLE c_forum_forum CHANGE lp_id lp_id INT DEFAULT NULL');
+        $this->addSql('UPDATE c_forum_forum SET lp_id = NULL WHERE lp_id = 0');
+        if (false === $table->hasIndex('UNIQ_47A9C9968DFD1EF')) {
+            $this->addSql('ALTER TABLE c_forum_forum ADD UNIQUE INDEX UNIQ_47A9C9968DFD1EF (lp_id)');
+        }
+
+        if ($table->hasForeignKey('FK_47A9C9921BF9426')) {
+            $this->addSql('ALTER TABLE c_forum_forum DROP FOREIGN KEY FK_47A9C9921BF9426');
+        }
+
 
         $table = $schema->getTable('c_forum_thread');
         if ($table->hasForeignKey('FK_5DA7884C29CCBAD0')) {
@@ -97,6 +110,10 @@ class Version20170625153000 extends AbstractMigrationChamilo
             $this->addSql('CREATE UNIQUE INDEX UNIQ_EC3CD8091BAD783F ON c_course_description (resource_node_id)');
         }
 
+        if ($table->hasIndex('session_id')) {
+            $this->addSql('DROP INDEX session_id ON c_course_description');
+        }
+
         $table = $schema->getTable('c_notebook');
 
         if ($table->hasIndex('course')) {
diff --git a/src/CoreBundle/Migrations/Schema/V200/Version20170628122900.php b/src/CoreBundle/Migrations/Schema/V200/Version20170628122900.php
index f0191e493f..fa2d33e6bd 100644
--- a/src/CoreBundle/Migrations/Schema/V200/Version20170628122900.php
+++ b/src/CoreBundle/Migrations/Schema/V200/Version20170628122900.php
@@ -19,10 +19,16 @@ class Version20170628122900 extends AbstractMigrationChamilo
         if (false === $table->hasColumn('id')) {
             $this->addSql('ALTER TABLE access_url_rel_user MODIFY COLUMN access_url_id INT NOT NULL');
             $this->addSql('ALTER TABLE access_url_rel_user MODIFY COLUMN user_id INT NOT NULL');
-            $this->addSql('ALTER TABLE access_url_rel_user DROP PRIMARY KEY');
+            if ($table->hasPrimaryKey()) {
+                $this->addSql('ALTER TABLE access_url_rel_user DROP PRIMARY KEY');
+            }
+
             $this->addSql(
-                'ALTER TABLE access_url_rel_user ADD id INT AUTO_INCREMENT NOT NULL, CHANGE access_url_id access_url_id INT DEFAULT NULL, CHANGE user_id user_id INT DEFAULT NULL, ADD PRIMARY KEY (id);'
+                'ALTER TABLE access_url_rel_user ADD id INT AUTO_INCREMENT NOT NULL, ADD PRIMARY KEY (id)'
             );
+
+            $this->addSql('ALTER TABLE access_url_rel_user CHANGE access_url_id access_url_id INT DEFAULT NULL');
+            $this->addSql('ALTER TABLE access_url_rel_user CHANGE user_id user_id INT DEFAULT NULL');
         }
 
         if (false === $table->hasForeignKey('FK_85574263A76ED395')) {
diff --git a/src/CoreBundle/Migrations/Schema/V200/Version20180319145700.php b/src/CoreBundle/Migrations/Schema/V200/Version20180319145700.php
index d0c511e671..282e684ca8 100644
--- a/src/CoreBundle/Migrations/Schema/V200/Version20180319145700.php
+++ b/src/CoreBundle/Migrations/Schema/V200/Version20180319145700.php
@@ -53,8 +53,12 @@ class Version20180319145700 extends AbstractMigrationChamilo
                 ->addColumn('is_required', Types::BOOLEAN)
                 ->setDefault(false);
         }
-        if (false === $table->hasIndex('idx_survey_q_qid')) {
+        /*if (false === $table->hasIndex('idx_survey_q_qid')) {
             $this->addSql('CREATE INDEX idx_survey_q_qid ON c_survey_question (question_id)');
+        }*/
+
+        if ($table->hasIndex('idx_survey_q_qid')) {
+            $this->addSql('DROP INDEX idx_survey_q_qid ON c_survey_question;');
         }
 
         if (false === $table->hasColumn('parent_id')) {
diff --git a/src/CoreBundle/Migrations/Schema/V200/Version20181025064351.php b/src/CoreBundle/Migrations/Schema/V200/Version20181025064351.php
index f75918da56..f500c7edf6 100644
--- a/src/CoreBundle/Migrations/Schema/V200/Version20181025064351.php
+++ b/src/CoreBundle/Migrations/Schema/V200/Version20181025064351.php
@@ -193,8 +193,9 @@ class Version20181025064351 extends AbstractMigrationChamilo
         }
 
         $table = $schema->getTable('gradebook_result');
-        if ($table->hasIndex('idx_gb_uid_eid')) {
-            $this->addSql('');
+
+        if (false === $table->hasIndex('idx_gb_uid_eid')) {
+            $this->addSql('CREATE INDEX idx_gb_uid_eid ON gradebook_result (user_id, evaluation_id);');
         }
 
         if (false === $table->hasIndex('IDX_B88AEB67456C5646')) {
@@ -292,6 +293,13 @@ class Version20181025064351 extends AbstractMigrationChamilo
             );
         }
 
+        if (false === $table->hasForeignKey('FK_640C644912469DE2')) {
+            $this->addSql(
+                'ALTER TABLE gradebook_score_log ADD CONSTRAINT FK_640C644912469DE2 FOREIGN KEY (category_id) REFERENCES gradebook_category (id)'
+            );
+        }
+
+
         if (false === $table->hasIndex('IDX_640C644912469DE2')) {
             $this->addSql('CREATE INDEX IDX_640C644912469DE2 ON gradebook_score_log (category_id);');
         }
diff --git a/src/CoreBundle/Migrations/Schema/V200/Version20190110182615.php b/src/CoreBundle/Migrations/Schema/V200/Version20190110182615.php
index 18ebe5926a..98a4a9405f 100644
--- a/src/CoreBundle/Migrations/Schema/V200/Version20190110182615.php
+++ b/src/CoreBundle/Migrations/Schema/V200/Version20190110182615.php
@@ -42,6 +42,14 @@ class Version20190110182615 extends AbstractMigrationChamilo
             $this->addSql('CREATE INDEX IDX_F67ABBEB5DA1941 ON c_lp (asset_id);');
         }
 
+        if ($table->hasIndex('session')) {
+            $this->addSql('DROP INDEX session ON c_lp');
+        }
+
+        if ($table->hasIndex('course')) {
+            $this->addSql('DROP INDEX course ON c_lp');
+        }
+
         if (false === $table->hasColumn('accumulate_work_time')) {
             $this->addSql('ALTER TABLE c_lp ADD accumulate_work_time INT DEFAULT 0 NOT NULL');
         }
diff --git a/src/CoreBundle/Migrations/Schema/V200/Version20201215072918.php b/src/CoreBundle/Migrations/Schema/V200/Version20201215072918.php
index 8af96468b1..bb9c60fbc4 100644
--- a/src/CoreBundle/Migrations/Schema/V200/Version20201215072918.php
+++ b/src/CoreBundle/Migrations/Schema/V200/Version20201215072918.php
@@ -48,7 +48,6 @@ final class Version20201215072918 extends AbstractMigrationChamilo
         $q = $em->createQuery('SELECT c FROM Chamilo\CoreBundle\Entity\Course c');
         /** @var Course $course */
         foreach ($q->toIterable() as $course) {
-            $counter = 1;
             $courseId = $course->getId();
             $course = $courseRepo->find($courseId);
 
@@ -83,6 +82,7 @@ final class Version20201215072918 extends AbstractMigrationChamilo
                     $em->flush();
                     continue;
                 }
+
                 // Assign parent.
                 $parent = null;
                 if (!empty($eventData['parent_event_id'])) {
@@ -95,6 +95,9 @@ final class Version20201215072918 extends AbstractMigrationChamilo
                 if (false === $result) {
                     continue;
                 }
+
+                $this->fixItemProperty('calendar_event', $eventRepo, $course, $admin, $event, $parent);
+
                 $em->persist($event);
                 $em->flush();
             }
diff --git a/src/CoreBundle/Migrations/Schema/V200/Version20201216124011.php b/src/CoreBundle/Migrations/Schema/V200/Version20201216124011.php
index d591744339..3f679eecbd 100644
--- a/src/CoreBundle/Migrations/Schema/V200/Version20201216124011.php
+++ b/src/CoreBundle/Migrations/Schema/V200/Version20201216124011.php
@@ -93,7 +93,7 @@ final class Version20201216124011 extends AbstractMigrationChamilo
             $sql = "SELECT * FROM c_student_publication
                     WHERE
                           contains_file = 1 AND
-                          c_id = $courseId AND
+                          c_id = $courseId
                     ORDER BY iid";
             $result = $connection->executeQuery($sql);
             $items = $result->fetchAllAssociative();
diff --git a/src/CoreBundle/Migrations/Schema/V200/Version20210221082033.php b/src/CoreBundle/Migrations/Schema/V200/Version20210221082033.php
index 2e97488157..9b7359532c 100644
--- a/src/CoreBundle/Migrations/Schema/V200/Version20210221082033.php
+++ b/src/CoreBundle/Migrations/Schema/V200/Version20210221082033.php
@@ -41,11 +41,11 @@ class Version20210221082033 extends AbstractMigrationChamilo
             $items = $result->fetchAllAssociative();
             foreach ($items as $itemData) {
                 $id = $itemData['iid'];
+                $path = $itemData['preview_image'];
                 $lp = $lpRepo->find($id);
-                if ($lp && !empty($lp->getPreviewImage())) {
-                    $path = $lp->getPreviewImage();
+                if ($lp && !empty($path)) {
                     $filePath = $rootPath.'/app/courses/'.$course->getDirectory().'/upload/learning_path/images/'.$path;
-                    if (file_exists($rootPath)) {
+                    if (file_exists($rootPath) && !is_dir($filePath)) {
                         $this->addLegacyFileToResource($filePath, $lpRepo, $lp, $lp->getIid(), $path);
                         $em->persist($lp);
                         $em->flush();
diff --git a/src/CourseBundle/Entity/CCalendarEventRepeat.php b/src/CourseBundle/Entity/CCalendarEventRepeat.php
index 270e5cc1f0..4977a3a6af 100644
--- a/src/CourseBundle/Entity/CCalendarEventRepeat.php
+++ b/src/CourseBundle/Entity/CCalendarEventRepeat.php
@@ -28,12 +28,10 @@ class CCalendarEventRepeat
     protected $iid;
 
     /**
-     * @var CCalendarEvent
-     *
      * @ORM\ManyToOne(targetEntity="Chamilo\CourseBundle\Entity\CCalendarEvent", inversedBy="repeatEvents")
      * @ORM\JoinColumn(name="cal_id", referencedColumnName="iid")
      */
-    protected $event;
+    protected CCalendarEvent $event;
 
     /**
      * @var string
@@ -67,10 +65,8 @@ class CCalendarEventRepeat
      * Set calType.
      *
      * @param string $calType
-     *
-     * @return CCalendarEventRepeat
      */
-    public function setCalType($calType)
+    public function setCalType($calType): self
     {
         $this->calType = $calType;
 
@@ -91,10 +87,8 @@ class CCalendarEventRepeat
      * Set calEnd.
      *
      * @param int $calEnd
-     *
-     * @return CCalendarEventRepeat
      */
-    public function setCalEnd($calEnd)
+    public function setCalEnd($calEnd): self
     {
         $this->calEnd = $calEnd;
 
@@ -115,10 +109,8 @@ class CCalendarEventRepeat
      * Set calFrequency.
      *
      * @param int $calFrequency
-     *
-     * @return CCalendarEventRepeat
      */
-    public function setCalFrequency($calFrequency)
+    public function setCalFrequency($calFrequency): self
     {
         $this->calFrequency = $calFrequency;
 
@@ -139,10 +131,8 @@ class CCalendarEventRepeat
      * Set calDays.
      *
      * @param string $calDays
-     *
-     * @return CCalendarEventRepeat
      */
-    public function setCalDays($calDays)
+    public function setCalDays($calDays): self
     {
         $this->calDays = $calDays;
 
diff --git a/src/CourseBundle/Entity/CForumForum.php b/src/CourseBundle/Entity/CForumForum.php
index ca2203c579..44e6d3ff87 100644
--- a/src/CourseBundle/Entity/CForumForum.php
+++ b/src/CourseBundle/Entity/CForumForum.php
@@ -77,12 +77,10 @@ class CForumForum extends AbstractResource implements ResourceInterface
     /**
      * @Gedmo\SortableGroup
      *
-     * @var CForumCategory|null
-     *
      * @ORM\ManyToOne(targetEntity="Chamilo\CourseBundle\Entity\CForumCategory", inversedBy="forums")
      * @ORM\JoinColumn(name="forum_category", referencedColumnName="iid", nullable=true, onDelete="SET NULL")
      */
-    protected $forumCategory;
+    protected ?CForumCategory $forumCategory;
 
     /**
      * @var int
@@ -187,7 +185,7 @@ class CForumForum extends AbstractResource implements ResourceInterface
      * @ORM\OneToOne(targetEntity="Chamilo\CourseBundle\Entity\CLp", inversedBy="forum")
      * @ORM\JoinColumn(name="lp_id", referencedColumnName="iid", nullable=true)
      */
-    protected $lp;
+    protected ?CLp $lp;
 
     /**
      * @var bool
@@ -210,9 +208,6 @@ class CForumForum extends AbstractResource implements ResourceInterface
      */
     protected $posts;
 
-    /**
-     * CForumForum constructor.
-     */
     public function __construct()
     {
         $this->threads = new ArrayCollection();