Issue #567148 by jcnventura, Damien Tournoud, greenrover33: Use ONLY_FULL_GROUP_BY for MySQL

core/lib/Drupal/Core/Database/Driver/mysql/Connection.php

@@ -113,7 +113,7 @@ public static function open(array &$connection_options = array()) {
       'init_commands' => array(),
     );
     $connection_options['init_commands'] += array(
-      'sql_mode' => "SET sql_mode = 'ANSI,STRICT_TRANS_TABLES,STRICT_ALL_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER'",
+      'sql_mode' => "SET sql_mode = 'ANSI,STRICT_TRANS_TABLES,STRICT_ALL_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,ONLY_FULL_GROUP_BY'",
     );
     // Execute initial commands.
     foreach ($connection_options['init_commands'] as $sql) {

index.php

@@ -15,7 +15,7 @@
 use Symfony\Component\HttpFoundation\Response;
 
 $autoloader = require_once 'autoload.php';
-
+require_once 'files.php';
 try {
 
   $request = Request::createFromGlobals();