diff --git a/libraries/DatabaseInterface.class.php b/libraries/DatabaseInterface.class.php
index 3c7e668b45..128cf61ffc 100644
--- a/libraries/DatabaseInterface.class.php
+++ b/libraries/DatabaseInterface.class.php
@@ -478,6 +478,24 @@ class PMA_DatabaseInterface
             foreach ($tables as $one_database_name => $one_database_tables) {
                 uksort($one_database_tables, 'strnatcasecmp');
 
+                if ($sort_order == 'DESC') {
+                    $one_database_tables = array_reverse($one_database_tables);
+                }
+                $tables[$one_database_name] = $one_database_tables;
+            }
+        } else if ($sort_by == 'Data_length') { // Size = Data_length + Index_length
+            foreach ($tables as $one_database_name => $one_database_tables) {
+                uasort(
+                    $one_database_tables,
+                    function($a, $b) {
+                        $aLength = $a['Data_length'] + $a['Index_length'];
+                        $bLength = $b['Data_length'] + $b['Index_length'];
+                        return ($aLength == $bLength)
+                            ? 0
+                            : ($aLength < $bLength) ? -1 : 1;
+                    }
+                );
+
                 if ($sort_order == 'DESC') {
                     $one_database_tables = array_reverse($one_database_tables);
                 }