php - 使用授权时mysql子查询错误

Question

当我运行这个查询时，MySQL 给了我一个错误：

mysqli_query($connect,"GRANT SELECT,INSERT ON myblog.*
    TO '$username'@'localhost' IDENTIFIED BY 
    (SELECT user_password from users where user_name = '$username')") 
or die("fail to grant ".mysqli_error($connect));

这个查询有什么问题？有没有更好的解决方案？

Answer 1

MySQL 不支持外部语句为GRANT.

A subquery's outer statement can be any one of: SELECT, INSERT, UPDATE, DELETE, SET, or DO.

编辑：取自MySQL docs on subqueries。