MySQL参数解析 password_require_current

password_require_current：

作用范围：Global

动态修改：Yes

取值范围：ON，OFF

默认值：OFF

来看下面的示例，password_require_current=ON设置下，修改密码没有指定旧密码，报错，使用replace子句指定旧密码，再次执行，成功。

mysql> alter user app@'%' identified by 'cC@12345678';

ERROR 3892 (HY000): Current password needs to be specified in the REPLACE clause in order to change it.

mysql> alter user app@'%' identified by 'cC@12345678' replace 'bB@12345678';

Query OK, 0 rows affected (0.01 sec)

除了使用参数password_require_current来控制全局的密码修改策略外，还可以在create user和alter user语句中，使用password require current子句单独控制某个用户的密码修改策略，如下所示：

create user app1@’%’ identified by ‘aA@12345678’ password require current;

create user app2@’%’ identified by ‘aA@12345678’ password require current optional;

create user app3@’%’ identified by ‘aA@12345678’ password require current default;