diff --git a/src/Connectors/Connector.php b/src/Connectors/Connector.php
index b942016..a40f07b 100755
--- a/src/Connectors/Connector.php
+++ b/src/Connectors/Connector.php
@@ -11,7 +11,6 @@
  */
 namespace Hyperf\Database\Connectors;
 
-use Doctrine\DBAL\Driver\PDO\Connection as PDOConnection;
 use Exception;
 use Hyperf\Database\DetectsLostConnections;
 use PDO;
@@ -104,10 +103,6 @@ public function setDefaultOptions(array $options)
      */
     protected function createPdoConnection($dsn, $username, $password, $options)
     {
-        if (class_exists(PDOConnection::class) && ! $this->isPersistentConnection($options)) {
-            return new PDOConnection($dsn, $username, $password, $options);
-        }
-
         return new PDO($dsn, $username, $password, $options);
     }
 
diff --git a/src/Connectors/MySqlConnector.php b/src/Connectors/MySqlConnector.php
index d383f13..e8bef21 100755
--- a/src/Connectors/MySqlConnector.php
+++ b/src/Connectors/MySqlConnector.php
@@ -137,9 +137,8 @@ protected function getHostDsn(array $config)
 
     /**
      * Set the modes for the connection.
-     * @param PDO $connection
      */
-    protected function setModes($connection, array $config)
+    protected function setModes(PDO $connection, array $config)
     {
         if (isset($config['modes'])) {
             $this->setCustomModes($connection, $config);