MySQL5.7 添加用戶、刪除用戶與授權

mysql -uroot -proot

MySQL5.7 mysql.user表沒有password字段改 authentication_string；

一. 創建用戶:

命令:CREATE USER ‘username‘@‘host‘ IDENTIFIED BY ‘password‘;

例子: CREATE USER ‘dog‘@‘localhost‘ IDENTIFIED BY ‘123456‘;

CREATE USER ‘dog2‘@‘localhost‘ IDENTIFIED BY ‘‘;

PS：username - 你將創建的用戶名,

host - 指定該用戶在哪個主機上可以登陸，此處的"localhost"，是指該用戶只能在本地登錄，不能在另外一臺機器上遠程登錄，如果想遠程登錄的話，將"localhost"改為"%"，表示在任何一臺電腦上都可以登錄;也可以指定某臺機器可以遠程登錄;

password - 該用戶的登陸密碼,密碼可以為空,如果為空則該用戶可以不需要密碼登陸服務器。

二.授權:

命令:GRANT privileges ON databasename.tablename TO ‘username‘@‘host‘

PS: privileges - 用戶的操作權限,如SELECT , INSERT , UPDATE 等(詳細列表見該文最後面).如果要授予所的權限則使用ALL.;databasename - 數據庫名,tablename-表名,如果要授予該用戶對所有數據庫和表的相應操作權限則可用*表示, 如*.*.

例子: GRANT SELECT, INSERT ON mq.* TO ‘dog‘@‘localhost‘;

三.創建用戶同時授權

mysql> grant all privileges on mq.* to [email protected] identified by ‘1234‘;
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)

PS:必須執行flush privileges;

否則登錄時提示：ERROR 1045 (28000): Access denied for user ‘user‘@‘localhost‘ (using password: YES )

四.設置與更改用戶密碼

命令:SET PASSWORD FOR ‘username‘@‘host‘ = PASSWORD(‘newpassword‘);

例子: SET PASSWORD FOR ‘dog2‘@‘localhost‘ = PASSWORD("dog");

五.撤銷用戶權限

命令: REVOKE privilege ON databasename.tablename FROM ‘username‘@‘host‘;

說明: privilege, databasename, tablename - 同授權部分.

例子: REVOKE SELECT ON mq.* FROM ‘dog2‘@‘localhost‘;

PS: 假如你在給用戶‘dog‘@‘localhost‘‘授權的時候是這樣的(或類似的):GRANT SELECT ON test.user TO ‘dog‘@‘localhost‘, 則在使用REVOKE SELECT ON *.* FROM ‘dog‘@‘localhost‘;命令並不能撤銷該用戶對test數據庫中user表的SELECT 操作.相反,如果授權使用的是GRANT SELECT ON *.* TO ‘dog‘@‘localhost‘;則REVOKE SELECT ON test.user FROM ‘dog‘@‘localhost‘;命令也不能撤銷該用戶對test數據庫中user表的Select 權限.

具體信息可以用命令SHOW GRANTS FOR ‘dog‘@‘localhost‘; 查看.

六.刪除用戶

命令: DROP USER ‘username‘@‘host‘;

七.查看用戶的授權

mysql> show grants for [email protected];
+---------------------------------------------+
| Grants for [email protected] |
+---------------------------------------------+
| GRANT USAGE ON *.* TO ‘dog‘@‘localhost‘ |
| GRANT INSERT ON `mq`.* TO ‘dog‘@‘localhost‘ |
+---------------------------------------------+
2 rows in set (0.00 sec)

PS:GRANT USAGE:mysql usage權限就是空權限，默認create user的權限，只能連庫，啥也不能幹

mysql> CREATE USER ‘root‘@‘192.168.1.17‘ IDENTIFIED BY ‘root‘;
Query OK, 0 rows affected (0.00 sec)

創建用戶

mysql> CREATE USER ‘root‘@‘%‘ IDENTIFIED BY ‘root‘;
Query OK, 0 rows affected (0.00 sec)

root 用戶可以在任何機器上登錄，且擁有任何表的任何權限

mysql> grant all privileges on *.* to [email protected]‘%‘ identified by ‘root‘;
Query OK, 0 rows affected, 1 warning (0.00 sec)

1. mysql> set global validate_password_policy=0;
2. Query OK, 0 rows affected (0.05 sec)
4. mysql>
5. mysql>
6. mysql> set global validate_password_mixed_case_count=0;
7. Query OK, 0 rows affected (0.00 sec)
9. mysql> set global validate_password_number_count=3;
10. Query OK, 0 rows affected (0.00 sec)
12. mysql> set global validate_password_special_char_count=0;
13. Query OK, 0 rows affected (0.00 sec)
15. mysql> set global validate_password_length=3;
16. Query OK, 0 rows affected (0.00 sec)
18. mysql> SHOW VARIABLES LIKE ‘validate_password%‘;
19. +--------------------------------------+-------+
20. | Variable_name | Value |
21. +--------------------------------------+-------+
22. | validate_password_dictionary_file | |
23. | validate_password_length | 3 |
24. | validate_password_mixed_case_count | 0 |
25. | validate_password_number_count | 3 |
26. | validate_password_policy | LOW |
27. | validate_password_special_char_count | 0 |
28. +--------------------------------------+-------+
29. 6 rows in set (0.00 sec)

FLUSH PRIVILEGES;

4）修改簡單密碼：

1. mysql> SET PASSWORD FOR ‘root‘@‘localhost‘ = PASSWORD(‘123‘);
2. Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql 5.7 學習