Mysql5.7后的password加密和md5 5.7之后
password函数旧版16位，新版41位，可⽤select password(‘123456’)查看。
md5加密算法，只有16位和32位两种
authentication_string
且5.7之后移除了password，它采⽤了新的算法
5.7之前
mysql> select user,host,password from mysql.user;
ERROR 1054 (42S22): Unknown column 'password' in 'field list'
5.7之后
mysql> select user,host,authentication_string from mysql.user;
+------+-----------+-------------------------------------------+
| user | host      | authentication_string                    |
+------+-----------+-------------------------------------------+
| root | localhost | *8A7993B6A9F0539BBE570DB3FD66FC580093FB05 |
| root | %        | *8A7993B6A9F0539BBE570DB3FD66FC580093FB05 |
+------+-----------+-------------------------------------------+
2 rows in set (0.00 sec)
在5.7中
PASSWORD() （已弃⽤5.7.6） 计算并返回密码字符串
在8.0中
PASSWORD(str)mysql下载32位
This function was removed in MySQL 8.0.11.