diff --git a/be/src/Controller/PostsController.php b/be/src/Controller/PostsController.php
index 461da3a6..f3db0824 100644
--- a/be/src/Controller/PostsController.php
+++ b/be/src/Controller/PostsController.php
@@ -87,26 +87,15 @@ public function query(Request $request): array
         $this->stopwatch->stop('fillWithParentPost');
 
         $this->stopwatch->start('queryUsers');
-        $latestRepliersId = $result['threads']->map(fn(Thread $thread) => $thread->getLatestReplierId());
-        $latestRepliers = collect()
-            ->concat($this->latestReplierRepository->createQueryBuilder('t')
-                ->where('t.id IN (:ids)')->setParameter('ids', $latestRepliersId)
-                ->andWhere('t.uid IS NOT NULL')
-                ->select('t.id', 't.uid', 't.createdAt', 't.updatedAt') // removeSelect('t.name', 't.displayName')
-                ->getQuery()->getResult())
-            ->concat($this->latestReplierRepository->createQueryBuilder('t')
-                ->where('t.id IN (:ids)')->setParameter('ids', $latestRepliersId)
-                ->andWhere('t.uid IS NULL')
-                ->getQuery()->getResult());
+        $latestRepliers = $this->latestReplierRepository->getLatestRepliersWithoutNameWhenHasUid(
+            $result['threads']->map(fn(Thread $thread) => $thread->getLatestReplierId()),
+        );
         $uids = collect($result)
             ->only(Helper::POST_TYPES_PLURAL)
             ->flatMap(static fn(Collection $posts) => $posts->map(fn(Post $post) => $post->getAuthorUid()))
-            ->concat($latestRepliers->pluck('uid'))
-            ->filter()->unique(); // remove NULLs
-        $users = collect($this->userRepository->createQueryBuilder('t')
-            ->where('t.uid IN (:uids)')
-            ->setParameter('uids', $uids)
-            ->getQuery()->getResult());
+            ->concat($latestRepliers->pluck('uid')->filter()) // filter() will remove NULLs
+            ->unique();
+        $users = collect($this->userRepository->getUsers($uids));
         $this->stopwatch->stop('queryUsers');
 
         $this->stopwatch->start('queryUserRelated');
@@ -127,10 +116,7 @@ public function query(Request $request): array
                 ...$query->getResultPages(),
                 ...Arr::except($result, ['fid', ...Helper::POST_TYPES_PLURAL]),
             ],
-            'forum' => $this->forumRepository->createQueryBuilder('t')
-                ->where('t.fid = :fid')->setParameter('fid', $fid)
-                ->select('t.fid', 't.name')->setMaxResults(1)
-                ->getQuery()->getSingleResult(),
+            'forum' => $this->forumRepository->getForum($fid),
             'threads' => $query->reOrderNestedPosts($query->nestPostsWithParent(...$result)),
             'users' => $users,
             'latestRepliers' => $latestRepliers,
diff --git a/be/src/PostsQuery/BaseQuery.php b/be/src/PostsQuery/BaseQuery.php
index 94872988..17ca3492 100644
--- a/be/src/PostsQuery/BaseQuery.php
+++ b/be/src/PostsQuery/BaseQuery.php
@@ -179,10 +179,7 @@ static function (string $postIDName) use ($result): array {
         /** @var Collection<int, int> $parentThreadsID parent tid of all replies and their sub replies */
         $parentThreadsID = $replies->pluck('tid')->concat($subReplies->pluck('tid'))->unique();
         /** @var Collection<int, Thread> $threads */
-        $threads = collect($postModels['thread']->createQueryBuilder('t')
-            ->where('t.tid IN (:tids)')
-            ->setParameter('tids', $parentThreadsID->concat($tids))
-            ->getQuery()->getResult())
+        $threads = collect($postModels['thread']->getPosts($parentThreadsID->concat($tids)))
         ->each(static fn(Thread $thread) =>
             $thread->setIsMatchQuery($tids->contains($thread->getTid())));
         $this->stopwatch->stop('fillWithThreadsFields');
@@ -191,31 +188,23 @@ static function (string $postIDName) use ($result): array {
         /** @var Collection<int, int> $parentRepliesID parent pid of all sub replies */
         $parentRepliesID = $subReplies->pluck('pid')->unique();
         $allRepliesId = $parentRepliesID->concat($pids);
-        $replies = collect($postModels['reply']->createQueryBuilder('t')
-            ->where('t.pid IN (:pids)')->setParameter('pids', $allRepliesId)
-            ->getQuery()->getResult())
+        $replies = collect($postModels['reply']->getPosts($allRepliesId))
         ->each(static fn(Reply $reply) =>
             $reply->setIsMatchQuery($pids->contains($reply->getPid())));
         $this->stopwatch->stop('fillWithRepliesFields');
 
         $this->stopwatch->start('fillWithSubRepliesFields');
-        $subReplies = collect($postModels['subReply']->createQueryBuilder('t')
-            ->where('t.spid IN (:spids)')->setParameter('spids', $spids)
-            ->getQuery()->getResult());
+        $subReplies = collect($postModels['subReply']->getPosts($spids));
         $this->stopwatch->stop('fillWithSubRepliesFields');
 
         $this->stopwatch->start('parsePostContentProtoBufBytes');
         // not using one-to-one association due to relying on PostRepository->getTableNameSuffix()
-        $replyContents = collect($this->postRepositoryFactory->newReplyContent($fid)->createQueryBuilder('t')
-                ->where('t.pid IN (:pids)')->setParameter('pids', $allRepliesId)
-                ->getQuery()->getResult())
+        $replyContents = collect($this->postRepositoryFactory->newReplyContent($fid)->getPosts($allRepliesId))
             ->mapWithKeys(fn(ReplyContent $content) => [$content->getPid() => $content->getContent()]);
         $replies->each(fn(Reply $reply) =>
             $reply->setContent($replyContents->get($reply->getPid())));
 
-        $subReplyContents = collect($this->postRepositoryFactory->newSubReplyContent($fid)->createQueryBuilder('t')
-                ->where('t.spid IN (:spids)')->setParameter('spids', $spids)
-                ->getQuery()->getResult())
+        $subReplyContents = collect($this->postRepositoryFactory->newSubReplyContent($fid)->getPosts($spids))
             ->mapWithKeys(fn(SubReplyContent $content) => [$content->getSpid() => $content->getContent()]);
         $subReplies->each(fn(SubReply $subReply) =>
             $subReply->setContent($subReplyContents->get($subReply->getSpid())));
diff --git a/be/src/PostsQuery/IndexQuery.php b/be/src/PostsQuery/IndexQuery.php
index 265f31d1..0a728b51 100644
--- a/be/src/PostsQuery/IndexQuery.php
+++ b/be/src/PostsQuery/IndexQuery.php
@@ -50,18 +50,14 @@ public function query(QueryParams $params, ?string $cursor): void
                 ->only($postTypes)
                 ->transform(static fn(PostRepository $repository) => $repository->selectCurrentAndParentPostID());
         $getFidByPostIDParam = function (string $postIDName, int $postID): int {
-            $counts = collect($this->forumRepository->getOrderedForumsId())
-                ->map(fn(int $fid) => $this->postRepositoryFactory
+            $postExistencesKeyByFid = collect($this->forumRepository->getOrderedForumsId())
+                ->mapWithKeys(fn(int $fid) => [$fid => $this->postRepositoryFactory
                     ->new($fid, Helper::POST_ID_TO_TYPE[$postIDName])
-                    ->createQueryBuilder('t')
-                    ->select("$fid AS fid", 'COUNT(t) AS count')
-                    ->where("t.$postIDName = :postID")
-                    ->setParameter('postID', $postID)
-                    ->getQuery()->getSingleResult())
-                ->where('count', '!=', 0);
-            Helper::abortAPIIf(50001, $counts->count() > 1);
-            Helper::abortAPIIf(40401, $counts->count() === 0);
-            return $counts->pluck('fid')->first();
+                    ->isPostExists($postID)])
+                ->filter(fn(bool $isExists) => $isExists);
+            Helper::abortAPIIf(50001, $postExistencesKeyByFid->count() > 1);
+            Helper::abortAPIIf(40401, $postExistencesKeyByFid->count() === 0);
+            return $postExistencesKeyByFid->keys()[0];
         };
 
         if (\array_key_exists('fid', $flatParams)) {
diff --git a/be/src/Repository/ForumRepository.php b/be/src/Repository/ForumRepository.php
index e8f9fd33..88e6af10 100644
--- a/be/src/Repository/ForumRepository.php
+++ b/be/src/Repository/ForumRepository.php
@@ -35,4 +35,11 @@ public function isForumExists(int $fid): bool
             ->setParameter('fid', $fid)
             ->getOneOrNullResult(AbstractQuery::HYDRATE_SINGLE_SCALAR) === 1;
     }
+
+    public function getForum(int $fid): Forum
+    {
+        return $this->getEntityManager()
+            ->createQuery(/** @lang DQL */'SELECT t.fid, t.name FROM App\Entity\Forum t WHERE t.fid = :fid')
+            ->setMaxResults(1)->setParameter('fid', $fid)->getSingleResult();
+    }
 }
diff --git a/be/src/Repository/LatestReplierRepository.php b/be/src/Repository/LatestReplierRepository.php
index a9861b27..b6f1c113 100644
--- a/be/src/Repository/LatestReplierRepository.php
+++ b/be/src/Repository/LatestReplierRepository.php
@@ -5,6 +5,7 @@
 use App\Entity\LatestReplier;
 use Doctrine\Bundle\DoctrineBundle\Repository\ServiceEntityRepository;
 use Doctrine\Persistence\ManagerRegistry;
+use Illuminate\Support\Collection;
 
 class LatestReplierRepository extends ServiceEntityRepository
 {
@@ -12,4 +13,21 @@ public function __construct(ManagerRegistry $registry)
     {
         parent::__construct($registry, LatestReplier::class);
     }
+
+    public function getLatestRepliersWithoutNameWhenHasUid(\ArrayAccess $latestRepliersId): Collection
+    {
+        $entityManager = $this->getEntityManager();
+        return collect($entityManager->createQuery(<<<'DQL'
+                SELECT t.id, t.uid, t.createdAt, t.updatedAt
+                FROM App\Entity\LatestReplier t
+                WHERE t.id IN (:ids) AND t.uid IS NOT NULL
+                DQL) // removeSelect('t.name', 't.displayName')
+                ->setParameter('ids', $latestRepliersId)->getResult())
+            ->concat(
+                $entityManager->createQuery(<<<'DQL'
+                SELECT t FROM App\Entity\LatestReplier t
+                WHERE t.id IN (:ids) AND t.uid IS NULL
+                DQL)->setParameter('ids', $latestRepliersId)->getResult(),
+            );
+    }
 }
diff --git a/be/src/Repository/Post/Content/ReplyContentRepository.php b/be/src/Repository/Post/Content/ReplyContentRepository.php
index b73941ee..f8c8180d 100644
--- a/be/src/Repository/Post/Content/ReplyContentRepository.php
+++ b/be/src/Repository/Post/Content/ReplyContentRepository.php
@@ -23,4 +23,13 @@ protected function getTableNameSuffix(): string
     {
         return 'reply_content';
     }
+
+    public function getPosts(\ArrayAccess $postsId): array
+    {
+        return $this->createQueryWithParam(
+            /** @lang DQL */'SELECT t FROM App\Entity\Post\Content\ReplyContent t WHERE t.pid IN (:pid)',
+            'pid',
+            $postsId
+        )->getResult();
+    }
 }
diff --git a/be/src/Repository/Post/Content/SubReplyContentRepository.php b/be/src/Repository/Post/Content/SubReplyContentRepository.php
index ad804160..e4490b2d 100644
--- a/be/src/Repository/Post/Content/SubReplyContentRepository.php
+++ b/be/src/Repository/Post/Content/SubReplyContentRepository.php
@@ -23,4 +23,13 @@ protected function getTableNameSuffix(): string
     {
         return 'subReply_content';
     }
+    
+    public function getPosts(\ArrayAccess $postsId): array
+    {
+        return $this->createQueryWithParam(
+            /** @lang DQL */'SELECT t FROM App\Entity\Post\Content\SubReplyContent t WHERE t.spid IN (:spid)',
+            'spid',
+            $postsId
+        )->getResult();
+    }
 }
diff --git a/be/src/Repository/Post/PostRepository.php b/be/src/Repository/Post/PostRepository.php
index b15178bd..1d63a2d0 100644
--- a/be/src/Repository/Post/PostRepository.php
+++ b/be/src/Repository/Post/PostRepository.php
@@ -7,6 +7,7 @@
 use App\Entity\Post\Post;
 use App\Helper;
 use Doctrine\Bundle\DoctrineBundle\Repository\ServiceEntityRepository;
+use Doctrine\ORM\AbstractQuery;
 use Doctrine\ORM\EntityManagerInterface;
 use Doctrine\ORM\QueryBuilder;
 use Doctrine\Persistence\ManagerRegistry;
@@ -47,4 +48,19 @@ public function selectCurrentAndParentPostID(): QueryBuilder
             ->map(static fn(string $postIDField) => "t.$postIDField")
             ->all());
     }
+
+    abstract public function getPosts(\ArrayAccess $postsId): array;
+
+    protected function createQueryWithParam(string $dql, string $paramName, int|\ArrayAccess $paramValue): AbstractQuery
+    {
+        return $this->getEntityManager()->createQuery($dql)->setParameter($paramName, $paramValue);
+    }
+
+    abstract public function isPostExists(int $postId): bool;
+
+    protected function isPostExistsWrapper(int $postId, string $dql, string $postIdParamName): bool
+    {
+        return $this->createQueryWithParam($dql, $postIdParamName, $postId)
+                ->getOneOrNullResult(AbstractQuery::HYDRATE_SINGLE_SCALAR) === 1;
+    }
 }
diff --git a/be/src/Repository/Post/ReplyRepository.php b/be/src/Repository/Post/ReplyRepository.php
index 75b2f55d..a1f25774 100644
--- a/be/src/Repository/Post/ReplyRepository.php
+++ b/be/src/Repository/Post/ReplyRepository.php
@@ -22,4 +22,22 @@ protected function getTableNameSuffix(): string
     {
         return 'reply';
     }
+    
+    public function getPosts(\ArrayAccess $postsId): array
+    {
+        return $this->createQueryWithParam(
+            /** @lang DQL */'SELECT t FROM App\Entity\Post\Reply t WHERE t.pid IN (:pid)',
+            'pid',
+            $postsId
+        )->getResult();
+    }
+    
+    public function isPostExists(int $postId): bool
+    {
+        return $this->isPostExistsWrapper(
+            $postId,
+            /** @lang DQL */'SELECT 1 FROM App\Entity\Post\Reply t WHERE t.pid = :pid',
+            'pid'
+        );
+    }
 }
diff --git a/be/src/Repository/Post/SubReplyRepository.php b/be/src/Repository/Post/SubReplyRepository.php
index 2b461b36..60a118a6 100644
--- a/be/src/Repository/Post/SubReplyRepository.php
+++ b/be/src/Repository/Post/SubReplyRepository.php
@@ -22,4 +22,22 @@ protected function getTableNameSuffix(): string
     {
         return 'subReply';
     }
+    
+    public function getPosts(\ArrayAccess $postsId): array
+    {
+        return $this->createQueryWithParam(
+            /** @lang DQL */'SELECT t FROM App\Entity\Post\SubReply t WHERE t.spid IN (:spid)',
+            'spid',
+            $postsId
+        )->getResult();
+    }
+
+    public function isPostExists(int $postId): bool
+    {
+        return $this->isPostExistsWrapper(
+            $postId,
+            /** @lang DQL */'SELECT 1 FROM App\Entity\Post\SubReply t WHERE t.spid = :spid',
+            'spid'
+        );
+    }
 }
diff --git a/be/src/Repository/Post/ThreadRepository.php b/be/src/Repository/Post/ThreadRepository.php
index 17dde90c..93fdfbf1 100644
--- a/be/src/Repository/Post/ThreadRepository.php
+++ b/be/src/Repository/Post/ThreadRepository.php
@@ -23,6 +23,24 @@ protected function getTableNameSuffix(): string
         return 'thread';
     }
 
+    public function getPosts(\ArrayAccess $postsId): array
+    {
+        return $this->createQueryWithParam(
+            /** @lang DQL */'SELECT t FROM App\Entity\Post\Thread t WHERE t.tid IN (:tid)',
+            'tid',
+            $postsId
+        )->getResult();
+    }
+
+    public function isPostExists(int $postId): bool
+    {
+        return $this->isPostExistsWrapper(
+            $postId,
+            /** @lang DQL */'SELECT 1 FROM App\Entity\Post\Thread t WHERE t.tid = :tid',
+            'tid'
+        );
+    }
+
     public function getThreadsIdByChunks(int $chunkSize): array
     {
         // https://github.com/doctrine/orm/issues/3542
diff --git a/be/src/Repository/UserRepository.php b/be/src/Repository/UserRepository.php
index 783a8bc2..3b05a240 100644
--- a/be/src/Repository/UserRepository.php
+++ b/be/src/Repository/UserRepository.php
@@ -12,4 +12,11 @@ public function __construct(ManagerRegistry $registry)
     {
         parent::__construct($registry, User::class);
     }
+    
+    public function getUsers(array $usersId): array
+    {
+        return $this->getEntityManager()
+            ->createQuery(/** @lang DQL */'SELECT t FROM App\Entity\User t WHERE t.uid IN (:usersId)')
+            ->setParameter('usersId', $usersId)->getResult();         
+    }
 }