Undefined class constant 'MYSQL_ATTR_USE_BUFFERED_QUERY'

The error that occurs is:
Fatal error: Undefined class constant 'MYSQL_ATTR_USE_BUFFERED_QUERY' in /www/drupalhead/includes/database/mysql/database.inc on line 31

Fatal error: Undefined class constant 'MYSQL_ATTR_USE_BUFFERED_QUERY' in /app/yiiext/ecshop_framework/cls/cls_pdo.php on line 216

需要在php.ini里面开启extension=php_pdo_mysql.dll

开启后重启服务器