MySQL开发知识：MySQL数据库用户权限管理

select * from mysql.user\G

*************************** 5. row ***************************
Host: localhost
User: root
Select_priv: Y
Insert_priv: Y
Update_priv: Y
Delete_priv: Y
Create_priv: Y
Drop_priv: Y
Reload_priv: Y
Shutdown_priv: Y
Process_priv: Y
File_priv: Y
Grant_priv: Y
References_priv: Y
Index_priv: Y
Alter_priv: Y
Show_db_priv: Y
Super_priv: Y
Create_tmp_table_priv: Y
Lock_tables_priv: Y
Execute_priv: Y
Repl_slave_priv: Y
Repl_client_priv: Y
Create_view_priv: Y
Show_view_priv: Y
Create_routine_priv: Y
Alter_routine_priv: Y
Create_user_priv: Y
Event_priv: Y
Trigger_priv: Y
Create_tablespace_priv: Y
ssl_type:
ssl_cipher:
x509_issuer:
x509_subject:
max_questions: 0
max_updates: 0
max_connections: 0
max_user_connections: 0
plugin: mysql_native_password
authentication_string: *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9
password_expired: N
password_last_changed: 2020-02-05 22:46:27
password_lifetime: NULL
account_locked: N
Create_role_priv: Y
Drop_role_priv: Y
Password_reuse_history: NULL
Password_reuse_time: NULL
Password_require_current: NULL
User_attributes: NULL

主机名和用户名共同组成复合主键
Host 主机名,允许访问的客户端，*代表所有客户端都可以访问
User 用户名

create user 用户 identified by 明文密码
— 用户 用户名@主机地址
— 主机地址： ” 或者 %

create user ‘user1’@’%’ identified by ‘123456’;
— 查看mysql.user表中是否存在新用户
select user, host from mysql.user where user = ‘user1’;
+——-+——+
| user | host |
+——-+——+
| user1 | % |
+——-+——+

create user user2;

drop user 用户名@host;

mysql> drop user ‘user1’@’%’;
Query OK, 0 rows affected (0.01 sec)
mysql> select user, host from mysql.user where user = ‘user1’;
Empty set (0.00 sec)

set password for 用户 = password(明文密码);
set password for ‘user1’@’%’ = password(654321);
— mysql5.7后续版本，8.0可用
alter user ‘user1’@’%’ identified by ‘654321’;

update mysql.user set password = password(明文密码) where user = ” and host = ”;
update mysql.user set password = password(‘123456’) where user = ‘user1’ and host = ‘%’;
— 8.0报错
update mysql.user set authentication_string = password(‘123456’) where user = ‘user1’ and host = ‘%’;

grant 权限列表 on 数据库/*.表名/* to 用户

— 分配权限 不需要刷新，马上生效
grant select on mydatabase.my_student to ‘user1’@’%’;

revoke 权限列表 /all privileges on 数据库/*.表/* from 用户

— 回收权限，不需要刷新，马上生效
revoke all privileges on mydatabase.my_student from ‘user1’@’%’;

flush privileges;

# 停止服务
mysql.server stop;

# 停止不了可以直接杀死进程
ps aux|grep mysql
kill <pid>

# 重新启动服务,跳过权限
mysqld –skip-grant-tables

# 直接无用户名登录
mysql

alter user ‘root’@’localhost’ identified by ‘123456’;