数据库操作发生错误

错误代码: 1064

[错误信息]

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'AND pass = 1' at line 1

[SQL语句]

SELECT `cid`,`parentid`,`classname` FROM `gw_category` WHERE cid = AND pass = 1

[TRACE]