MySQL--创建用户

CREATE USER ‘username‘@‘hostname‘ IDENTIFIED BY ‘password‘; 

GRANT priv_type
ON object_type
TO ‘username‘@‘hostname‘
IDENTIFIED BY [PASSWORD] ‘password‘
[WITH GRANT OPTION]

[PASSWORD]是可选参数，IDENTIFIED BY PASSWORD 后跟的是加密后的密码，IDENTIFIED BY 后跟的是未加密的密码
GRANT USAGE ON *.* TO ‘cx‘@‘%‘ IDENTIFIED BY PASSWORD ‘*67CF1635475C64DE1C9608FEEE1AD307C4C2BC2F‘;
和
GRANT USAGE ON *.* TO ‘cx‘@‘%‘ IDENTIFIED BY ‘abc@123.com‘;
上面两条SQL效果一样，但推荐使用第一种方式，第二种方式的明文密码会被记录到binlog中，存在安全风险。

WITH GRANT OPTION 允许用户将自身拥有的权限授予他人。 
The WITH GRANT OPTION clause gives the user the ability to give to other users any privileges the user has at the specified privilege level.

对于hostname，可以使用%和_两种通配符，如：

GRANT ALL PRIVILEGES
ON *.* TO ‘gga1‘@‘%.mysql.com‘
IDENTIFIED BY ‘123@456‘
WITH GRANT OPTION;

%表示通配0到N个字符
_表示通配1个字符

#设置用户过期时间为60天过期
ALTER USER ‘gga‘@‘localhost‘ PASSWORD EXPIRE INTERVAL 60 DAY;