diff --git a/DataStorage/Database/Exception/InvalidDatabaseTypeException.php b/DataStorage/Database/Exception/InvalidDatabaseTypeException.php
new file mode 100644
index 000000000..8f3338823
--- /dev/null
+++ b/DataStorage/Database/Exception/InvalidDatabaseTypeException.php
@@ -0,0 +1,40 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 7.1
+ *
+ * @package    TBD
+ * @copyright  Dennis Eichhorn
+ * @license    OMS License 1.0
+ * @version    1.0.0
+ * @link       http://website.orange-management.de
+ */
+declare(strict_types = 1);
+
+namespace phpOMS\DataStorage\Database\Exception;
+
+/**
+ * Permission exception class.
+ *
+ * @package    Framework
+ * @license    OMS License 1.0
+ * @link       http://website.orange-management.de
+ * @since      1.0.0
+ */
+class InvalidDatabaseTypeException extends \InvalidArgumentException
+{
+    /**
+     * Constructor.
+     *
+     * @param string     $message Exception message
+     * @param int        $code    Exception code
+     * @param \Exception $previous Previous exception
+     *
+     * @since  1.0.0
+     */
+    public function __construct(string $message = '', int $code = 0, \Exception $previous = null)
+    {
+        parent::__construct('Invalid database type "' . $message . '".', $code, $previous);
+    }
+}
diff --git a/Module/ModuleManager.php b/Module/ModuleManager.php
index 8f68e05ff..94a25fe9f 100644
--- a/Module/ModuleManager.php
+++ b/Module/ModuleManager.php
@@ -17,6 +17,7 @@ namespace phpOMS\Module;
 use phpOMS\ApplicationAbstract;
 use phpOMS\Autoloader;
 use phpOMS\DataStorage\Database\DatabaseType;
+use phpOMS\DataStorage\Database\Exception\InvalidDatabaseTypeException;
 use phpOMS\Message\Http\Request;
 use phpOMS\Message\RequestAbstract;
 use phpOMS\System\File\PathException;
@@ -174,6 +175,9 @@ class ModuleManager
                     $sth->execute();
 
                     $this->uriLoad = $sth->fetchAll(\PDO::FETCH_GROUP);
+                    break;
+                default: 
+                    throw new InvalidDatabaseTypeException($this->app->dbPool->get('select')->getType());
             }
         }
 
@@ -198,6 +202,8 @@ class ModuleManager
                     $sth->execute();
                     $this->active = $sth->fetchAll(\PDO::FETCH_COLUMN);
                     break;
+                default: 
+                    throw new InvalidDatabaseTypeException($this->app->dbPool->get('select')->getType());
             }
         }
 
@@ -269,6 +275,8 @@ class ModuleManager
                     $sth->execute();
                     $this->installed = $sth->fetchAll(\PDO::FETCH_GROUP);
                     break;
+                default: 
+                    throw new InvalidDatabaseTypeException($this->app->dbPool->get('select')->getType());
             }
         }