diff --git a/core/lib/Drupal/Core/Cache/DatabaseBackend.php b/core/lib/Drupal/Core/Cache/DatabaseBackend.php
index d1e0060..311b236 100644
--- a/core/lib/Drupal/Core/Cache/DatabaseBackend.php
+++ b/core/lib/Drupal/Core/Cache/DatabaseBackend.php
@@ -8,9 +8,7 @@
 namespace Drupal\Core\Cache;
 
 use Drupal\Core\Database\Database;
-use Drupal\Core\Database\DatabaseExceptionWrapper;
-use Exception;
-use PDO;
+use Drupal\Core\Database\DatabaseException;
 
 /**
  * Defines a default cache implementation.
@@ -150,7 +148,7 @@ public function set($cid, $data, $expire = CacheBackendInterface::CACHE_PERMANEN
         ->fields($fields)
         ->execute();
     }
-    catch (DatabaseExceptionWrapper $e) {
+    catch (DatabaseException $e) {
       // If set() failed for whatever reason, then try to delete() to avoid a
       // stale cache.
       $this->delete($cid);
@@ -312,7 +310,7 @@ protected function checksumTags($flat_tags) {
 
     $query_tags = array_diff($flat_tags, array_keys($tag_cache));
     if ($query_tags) {
-      $db_tags = Database::getConnection()->query('SELECT tag, invalidations, deletions FROM {cache_tags} WHERE tag IN (:tags)', array(':tags' => $query_tags))->fetchAllAssoc('tag', PDO::FETCH_ASSOC);
+      $db_tags = Database::getConnection()->query('SELECT tag, invalidations, deletions FROM {cache_tags} WHERE tag IN (:tags)', array(':tags' => $query_tags))->fetchAllAssoc('tag', \PDO::FETCH_ASSOC);
       $tag_cache += $db_tags;
 
       // Fill static cache with empty objects for tags not found in the database.