diff --git a/lib/Alchemy/Phrasea/Collection/Factory/DbalCollectionRepositoryFactory.php b/lib/Alchemy/Phrasea/Collection/Factory/DbalCollectionRepositoryFactory.php
index c26ea68872..415c401851 100644
--- a/lib/Alchemy/Phrasea/Collection/Factory/DbalCollectionRepositoryFactory.php
+++ b/lib/Alchemy/Phrasea/Collection/Factory/DbalCollectionRepositoryFactory.php
@@ -48,11 +48,11 @@ class DbalCollectionRepositoryFactory implements CollectionRepositoryFactory
      */
     public function createRepositoryForDatabox($databoxId)
     {
-        $connection = $this->databoxConnectionProvider->getConnection($databoxId);
+        $databoxConnection = $this->databoxConnectionProvider->getConnection($databoxId);
 
         return new DbalCollectionRepository(
             $databoxId,
-            $connection,
+            $databoxConnection,
             $this->collectionReferenceRepository,
             $this->collectionFactory
         );
diff --git a/lib/Alchemy/Phrasea/Collection/Repository/CachedCollectionRepository.php b/lib/Alchemy/Phrasea/Collection/Repository/CachedCollectionRepository.php
index a7a414aee4..71e68aed02 100644
--- a/lib/Alchemy/Phrasea/Collection/Repository/CachedCollectionRepository.php
+++ b/lib/Alchemy/Phrasea/Collection/Repository/CachedCollectionRepository.php
@@ -56,7 +56,7 @@ final class CachedCollectionRepository implements CollectionRepository
      */
     public function findAll()
     {
-        $cacheKey = hash('sha256', $this->cacheKey);
+        $cacheKey = $this->getCacheKey();
         /** @var \collection[] $collections */
         $collections = $this->cache->fetch($cacheKey);
 
@@ -91,7 +91,7 @@ final class CachedCollectionRepository implements CollectionRepository
     {
         $this->repository->save($collection);
 
-        $cacheKey = hash('sha256', $this->cacheKey);
+        $cacheKey = $this->getCacheKey();
 
         $this->cache->delete($cacheKey);
     }
@@ -100,7 +100,7 @@ final class CachedCollectionRepository implements CollectionRepository
     {
         $this->repository->delete($collection);
 
-        $cacheKey = hash('sha256', $this->cacheKey);
+        $cacheKey = $this->getCacheKey();
 
         $this->cache->delete($cacheKey);
     }
@@ -109,4 +109,14 @@ final class CachedCollectionRepository implements CollectionRepository
     {
         $this->cache->save($key, $value);
     }
+
+    /**
+     * @return string
+     */
+    private function getCacheKey()
+    {
+        $cacheKey = 'collections:' . hash('sha256', $this->cacheKey);
+
+        return $cacheKey;
+    }
 }
diff --git a/lib/Alchemy/Phrasea/Collection/Repository/DbalCollectionRepository.php b/lib/Alchemy/Phrasea/Collection/Repository/DbalCollectionRepository.php
index 9a5c656ec8..24736a7adc 100644
--- a/lib/Alchemy/Phrasea/Collection/Repository/DbalCollectionRepository.php
+++ b/lib/Alchemy/Phrasea/Collection/Repository/DbalCollectionRepository.php
@@ -35,7 +35,7 @@ class DbalCollectionRepository implements CollectionRepository
     /**
      * @var Connection
      */
-    private $connection;
+    private $databoxConnection;
 
     /**
      * @var CollectionFactory
@@ -44,18 +44,18 @@ class DbalCollectionRepository implements CollectionRepository
 
     /**
      * @param $databoxId
-     * @param Connection $connection
+     * @param Connection $databoxConnection
      * @param CollectionReferenceRepository $referenceRepository
      * @param CollectionFactory $collectionFactory
      */
     public function __construct(
         $databoxId,
-        Connection $connection,
+        Connection $databoxConnection,
         CollectionReferenceRepository $referenceRepository,
         CollectionFactory $collectionFactory
     ) {
         $this->databoxId = (int) $databoxId;
-        $this->connection = $connection;
+        $this->databoxConnection = $databoxConnection;
         $this->referenceRepository = $referenceRepository;
         $this->collectionFactory = $collectionFactory;
     }
@@ -81,7 +81,7 @@ class DbalCollectionRepository implements CollectionRepository
         $parameters = [ 'collectionIds' => $parameters ];
         $parameterTypes = [ 'collectionIds' => Connection::PARAM_INT_ARRAY ];
 
-        $rows = $this->connection->fetchAll($query, $parameters, $parameterTypes);
+        $rows = $this->databoxConnection->fetchAll($query, $parameters, $parameterTypes);
 
         return $this->collectionFactory->createMany($this->databoxId, $references, $rows);
     }
@@ -99,7 +99,7 @@ class DbalCollectionRepository implements CollectionRepository
         }
 
         $query = self::$selectQuery . ' WHERE coll_id = :collectionId';
-        $row = $this->connection->fetchAssoc($query, [ ':collectionId' => $reference->getCollectionId() ]);
+        $row = $this->databoxConnection->fetchAssoc($query, [ ':collectionId' => $reference->getCollectionId() ]);
 
         if ($row !== false) {
             return $this->collectionFactory->create($this->databoxId, $reference, $row);
@@ -122,7 +122,7 @@ class DbalCollectionRepository implements CollectionRepository
         }
 
         $query = self::$selectQuery . ' WHERE coll_id = :collectionId';
-        $row = $this->connection->fetchAssoc($query, [ ':collectionId' => $reference->getCollectionId() ]);
+        $row = $this->databoxConnection->fetchAssoc($query, [ ':collectionId' => $reference->getCollectionId() ]);
 
         if ($row !== false) {
             return $this->collectionFactory->create($this->databoxId, $reference, $row);
@@ -154,10 +154,10 @@ class DbalCollectionRepository implements CollectionRepository
             $isInsert = false;
         }
 
-        $this->connection->executeQuery($query, $parameters);
+        $this->databoxConnection->executeQuery($query, $parameters);
 
         if ($isInsert) {
-            $collection->setCollectionId($this->connection->lastInsertId());
+            $collection->setCollectionId($this->databoxConnection->lastInsertId());
         }
     }
 
@@ -167,6 +167,6 @@ class DbalCollectionRepository implements CollectionRepository
             'collectionId' => $collection->getCollectionId()
         ];
 
-        $this->connection->executeQuery(self::$deleteQuery, $parameters);
+        $this->databoxConnection->executeQuery(self::$deleteQuery, $parameters);
     }
 }