diff --git a/db_multi_table_query.php b/db_multi_table_query.php
index a375bfab9c..d38c3112c4 100644
--- a/db_multi_table_query.php
+++ b/db_multi_table_query.php
@@ -53,6 +53,6 @@ $scripts = $header->getScripts();
 $scripts->addFile('vendor/jquery/jquery.md5.js');
 $scripts->addFile('db_multi_table_query.js');
 
-$QueryInstance = new MultiTableQuery($db);
+$QueryInstance = new MultiTableQuery($GLOBALS['dbi'], $db);
 
 $response->addHTML($QueryInstance->getFormHTML());
diff --git a/libraries/classes/Database/MultiTableQuery.php b/libraries/classes/Database/MultiTableQuery.php
index c64401fc0e..9a068eb6ed 100644
--- a/libraries/classes/Database/MultiTableQuery.php
+++ b/libraries/classes/Database/MultiTableQuery.php
@@ -7,6 +7,7 @@
  */
 namespace PhpMyAdmin\Database;
 
+use PhpMyAdmin\DatabaseInterface;
 use PhpMyAdmin\Template;
 
 /**
@@ -16,43 +17,81 @@ use PhpMyAdmin\Template;
  */
 class MultiTableQuery
 {
+    /**
+     * DatabaseInterface instance
+     *
+     * @access private
+     * @var DatabaseInterface
+     */
+    private $dbi;
+
     /**
      * Database name
      *
      * @access private
      * @var string
      */
-    private $_db;
+    private $db;
 
     /**
-     * Default no. of columns
+     * Default number of columns
      *
      * @access private
      * @var integer
      */
-    private $_default_no_of_columns;
+    private $defaultNoOfColumns;
 
-    public function __construct($db_name)
-    {
-        $this->_db = $db_name;
-        $this->_default_no_of_columns = 3;
+    /**
+     * Table names
+     *
+     * @access private
+     * @var array
+     */
+    private $tables;
+
+    /**
+     * Constructor
+     *
+     * @param DatabaseInterface $dbi                DatabaseInterface instance
+     * @param string            $dbName             Database name
+     * @param integer           $defaultNoOfColumns Default number of columns
+     */
+    public function __construct(
+        DatabaseInterface $dbi,
+        $dbName,
+        $defaultNoOfColumns = 3
+    ) {
+        $this->dbi = $dbi;
+        $this->db = $dbName;
+        $this->defaultNoOfColumns = $defaultNoOfColumns;
+
+        $this->tables = $this->dbi->getTables($this->db);
     }
 
+    /**
+     * Get HTML for columns
+     *
+     * @return string HTML with columns
+     */
     private function getColumnsHTML()
     {
-        $tables = $GLOBALS['dbi']->getTables($this->_db);
         return Template::get('database/multi_table_query/columns')->render([
-            'tables' => $tables,
-            'dbi' => $GLOBALS['dbi'],
-            'db' => $this->_db,
-            'default_no_of_columns' => $this->_default_no_of_columns,
+            'tables' => $this->tables,
+            'dbi' => $this->dbi,
+            'db' => $this->db,
+            'default_no_of_columns' => $this->defaultNoOfColumns,
         ]);
     }
 
+    /**
+     * Get Multi Table Query page HTML
+     *
+     * @return string Multi Table Query page HTML
+     */
     public function getFormHTML()
     {
         return Template::get('database/multi_table_query/form')->render([
-            'db' => $this->_db,
+            'db' => $this->db,
             'columns' => $this->getColumnsHTML(),
         ]);
     }