前言mysql 更新完密码，总是拒绝连接、登录失败?mysql8.0 不能通过直接修改 mysql.user 表来更改密码。正确更改密码的方式备注: 清空root密码
mysql8.0 不能通过直接修改 mysql.user 表来更改密码。
因为authentication_string字段下只能是mysql加密后的43位字符串密码，其他的导致错误。错误不报出，但是无法再登录mysql，总是会提示 无法认证。
参考：mysql8.0
mysql> use mysql;database changedmysql> update user set authentication_string="123456" where user="root";query ok, 1 row affected (0.39 sec)rows matched: 1 changed: 1 warnings: 0mysql> flush privileges; # 刷新保存query ok, 0 rows affected (0.13 sec)
mysql 5.7.9 之后取消了password 函数，authentication_string=password("123456") 会报错c:\windows\system32>mysql -u root -p
enter password: ******
error 1045 (28000): access denied for user ‘root’@‘localhost’ (using password: yes)
1234567891011121314
如果 你已经这样更改密码，并且导致了无法进入mysql。本人表示同情之时，还为了你提供了详细的解决方案。请查看本文备注：清空root 密码
正确更改密码的方式alter user 'root'@'localhost' identified with mysql_native_password by "your_password";mysql> use mysql;database changedmysql> alter user 'root'@'localhost' identifieed with mysql_native_password by "markjun";error 1064 (42000): 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 'identifieed with mysql_native_password by "markjun"' at line 1mysql> alter user 'root'@'localhost' identified with mysql_native_password by "markjun";query ok, 0 rows affected (0.18 sec)mysql> alter user 'root'@'localhost' identified with mysql_native_password by "123456";query ok, 0 rows affected (0.08 sec)mysql> select user, authentication_string from user;+------------------+------------------------------------------------------------------------+| user | authentication_string |+------------------+------------------------------------------------------------------------+| mysql.infoschema | $a$005$thisisacombinationofinvalidsaltandpasswordthatmustneverbrbeused || mysql.session | $a$005$thisisacombinationofinvalidsaltandpasswordthatmustneverbrbeused || mysql.sys | $a$005$thisisacombinationofinvalidsaltandpasswordthatmustneverbrbeused || root | *6bb4837eb74329105ee4568dda7dc67ed2ca2ad9 |+------------------+------------------------------------------------------------------------+4 rows in set (0.00 sec)mysql> flush privileges;query ok, 0 rows affected (0.38 sec)mysql> quit;byef:\mysql\mysql-8.0.13-winx64\bin>mysql -u root -penter password: *******...mysql>
备注: 清空root密码
停止 mysql 任务 net stop mysql
mysqld 命令 mysqld --console --skip-grant-tables --shared-memory
无密码进入mysql mysql -u root
清空root 密码 update user set authentication_string="" where user=“root”;
另一个终端无密码进入
f:\mysql\mysql-8.0.13-winx64\bin>mysql -u root -penter password: *******error 1045 (28000): access denied for user 'root'@'localhost' (using password: yes)f:\mysql\mysql-8.0.13-winx64\bin>mysql -u rootwelcome to the mysql monitor. commands end with ; or \g.your mysql connection id is 7...type 'help;' or '\h' for help. type '\c' to clear the current input statement.mysql> use mysql;database changedmysql> select user, authentication_string from user;+------------------+------------------------------------------------------------------------+| user | authentication_string |+------------------+------------------------------------------------------------------------+| mysql.infoschema | $a$005$thisisacombinationofinvalidsaltandpasswordthatmustneverbrbeused || mysql.session | $a$005$thisisacombinationofinvalidsaltandpasswordthatmustneverbrbeused || mysql.sys | $a$005$thisisacombinationofinvalidsaltandpasswordthatmustneverbrbeused || root | 123456 |+------------------+------------------------------------------------------------------------+4 rows in set (0.34 sec)mysql> update user set authentication_string="" where user="root";query ok, 1 row affected (0.20 sec)rows matched: 1 changed: 1 warnings: 0mysql> select user, authentication_string from user;+------------------+------------------------------------------------------------------------+| user | authentication_string |+------------------+------------------------------------------------------------------------+| mysql.infoschema | $a$005$thisisacombinationofinvalidsaltandpasswordthatmustneverbrbeused || mysql.session | $a$005$thisisacombinationofinvalidsaltandpasswordthatmustneverbrbeused || mysql.sys | $a$005$thisisacombinationofinvalidsaltandpasswordthatmustneverbrbeused || root | |+------------------+------------------------------------------------------------------------+4 rows in set (0.00 sec)mysql> flush privileges;query ok, 0 rows affected (0.10 sec)mysql> quit;bye
你可以通过停止 mysqld 进程、在运行 mysqld 的 cmd 终端中使用 ctrl+c 结束任务，或者直接关闭终端来结束 mysqld 任务。
需要先停止运行上述 mysqld 任务,否则报错
f:\mysql\mysql-8.0.13-winx64\bin>net start mysql
mysql 服务正在启动 .
mysql 服务无法启动。
服务没有报告任何错误。
请键入 net helpmsg 3534 以获得更多的帮助。
先停止上述 mysqld 任务
f:\mysql\mysql-8.0.13-winx64\bin>net start mysql
mysql 服务正在启动 ...
mysql 服务已经启动成功。
现在 mysql root 已经没有了密码
f:\mysql\mysql-8.0.13-winx64\bin>mysql -u root -p
enter password:
welcome to the mysql monitor.  commands end with ; or \g.
...
type 'help;' or '\h' for help. type '\c' to clear the current input statement.
mysql>
以上就是mysql8.0怎么正确修改密码的详细内容。