diff --git a/lib/Doctrine/DBAL/Query/QueryBuilder.php b/lib/Doctrine/DBAL/Query/QueryBuilder.php
index 12287daf944..46d7db7a21e 100644
--- a/lib/Doctrine/DBAL/Query/QueryBuilder.php
+++ b/lib/Doctrine/DBAL/Query/QueryBuilder.php
@@ -480,11 +480,12 @@ public function select($select = null)
      *         ->from('users', 'u')
      * </code>
      *
-     * @return self
+     * @return $this This QueryBuilder instance.
      */
     public function distinct() : self
     {
         $this->sqlParts['distinct'] = true;
+
         return $this;
     }
 
@@ -1117,7 +1118,7 @@ public function resetQueryPart($queryPartName)
      */
     private function getSQLForSelect()
     {
-        $query = 'SELECT ' . ($this->sqlParts['distinct'] ? 'DISTINCT ' : '') .         
+        $query = 'SELECT ' . ($this->sqlParts['distinct'] ? 'DISTINCT ' : '') .
                   implode(', ', $this->sqlParts['select']);
 
         $query .= ($this->sqlParts['from'] ? ' FROM ' . implode(', ', $this->getFromClauses()) : '')