Fatal error: Uncaught Error: Class "Drupal\Core\Database\Query\Upsert" not found in /home/www/drupal8/test/core/lib/Drupal/Core/Database/Driver/mysql/Upsert.php:10
Stack trace:
#0 {main}
thrown in /home/www/drupal8/test/core/lib/Drupal/Core/Database/Driver/mysql/Upsert.php on line 10