在CentOS7下添加MySQL用戶並設置相應權限

1.進入mysql命令行，輸入root及密碼

[root@localhost ~]# mysql -u root -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 19
Server version: 5.7.22 MySQL Community Server (GPL)
 
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
 
Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners.
 
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
 
mysql> 

2.用戶管理及權限設置
// 管理用戶

mysql> use mysql;
Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A
 
Database changed

 
//查詢用戶

mysql> select host,user from user;
+-----------+---------------+
| host      | user          |
+-----------+---------------+
| %         | root          |
| %         | test          |
| localhost | mysql.session |
| localhost | mysql.sys     |
| localhost | root          |
+-----------+---------------+
5 rows in set (0.00 sec)

 
//建立用戶（用戶：admin，密碼:123456）

mysql> create user admin identified by '123456';
Query OK, 0 rows affected (0.00 sec)

 
// 刪除用戶admin

mysql> drop user admin;
Query OK, 0 rows affected (0.00 sec)

 
// 從新建立用戶（用戶：admins，密碼:123456）

mysql> create user admins identified by '123456';
Query OK, 0 rows affected (0.00 sec)
 
mysql> select host, user from user;
+-----------+---------------+
| host      | user          |
+-----------+---------------+
| %         | admins        |
| %         | root          |
| %         | test          |
| localhost | mysql.session |
| localhost | mysql.sys     |
| localhost | root          |
+-----------+---------------+
6 rows in set (0.00 sec)
 
// 查看用戶admins的權限
mysql> show grants for admins;
+------------------------------------+
| Grants for admins@%                |
+------------------------------------+
| GRANT USAGE ON *.* TO 'admins'@'%' |
+------------------------------------+
1 row in set (0.00 sec)
 
// 賦予權限（給用戶admins，授予數據庫test的查詢權限）
mysql> grant select on test.* to admins;
Query OK, 0 rows affected (0.00 sec)
 
// 查看用戶admins的權限
mysql> show grants for admins;
+------------------------------------------+
| Grants for admins@%                      |
+------------------------------------------+
| GRANT USAGE ON *.* TO 'admins'@'%'       |
| GRANT SELECT ON `test`.* TO 'admins'@'%' |
+------------------------------------------+
2 rows in set (0.00 sec)
 
// 收回權限（對用戶admins，收回數據庫test的查詢權限）
mysql> revoke select on test.* from admins;
Query OK, 0 rows affected (0.01 sec)
 
// 查看用戶admins的權限
mysql> show grants for admins;
+------------------------------------+
| Grants for admins@%                |
+------------------------------------+
| GRANT USAGE ON *.* TO 'admins'@'%' |
+------------------------------------+
1 row in set (0.00 sec)
 
// 賦予權限（給用戶admins，授予數據庫test的查詢、更新、刪除、插入等權限）
mysql> grant select, update, delete, insert on test.* to admins;
Query OK, 0 rows affected (0.00 sec)
 
// 查看用戶admins的權限
mysql> show grants for admins;
+------------------------------------------------------------------+
| Grants for admins@%                                              |
+------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'admins'@'%'                               |
| GRANT SELECT, INSERT, UPDATE, DELETE ON `test`.* TO 'admins'@'%' |
+------------------------------------------------------------------+
2 rows in set (0.01 sec)
 
// 賦予權限（給用戶admins，授予數據庫test的新建表、刪除表或刪除數據庫等權限）
mysql> grant create,drop on test.* to admins;
Query OK, 0 rows affected (0.00 sec)
 
// 查看用戶admins的權限
mysql> show grants for admins;
+--------------------------------------------------------------------------------+
| Grants for admins@%                                                            |
+--------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'admins'@'%'                                             |
| GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP ON `test`.* TO 'admins'@'%' |
+--------------------------------------------------------------------------------+
2 rows in set (0.00 sec)
 
// 刷新權限（使設置的權限生效）
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
 
 
 
 
// 查看root的權限
mysql> show grants for root;
+-------------------------------------------+
| Grants for root@%                         |
+-------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' |
+-------------------------------------------+
1 row in set (0.00 sec)

如下是用戶能夠享受的常見可能權限的簡短列表。

ALL PRIVILEGES - 正如咱們前面所看到的，這將容許MySQL用戶訪問指定的數據庫（或者若是系統中沒有選擇數據庫）
CREATE-容許他們建立新的表或數據庫
DROP-容許他們刪除表或數據庫
DELETE-容許他們從表中刪除行
INSERT-容許它們向表中插入行
SELECT-容許他們使用Select命令來讀取數據庫
UPDATE-容許他們更新錶行
GRANT OPTION - 容許他們授予或刪除其餘用戶的權限
 

要向特定用戶提供權限，能夠使用此框架：

GRANT [type of permission] ON [database name].[table name] TO ‘[username]’@'localhost’;

若是要向其授予對任何數據庫或任何表的訪問權限，請確保在數據庫名稱或表名稱的地方放置星號（*）。
每次更新或更改權限時，請務必使用Flush Privileges命令。

若是您須要撤消權限，則結構與授予的結構幾乎相同：
REVOKE [type of permission] ON [database name].[table name] FROM ‘[username]’@‘localhost’;

正如您能夠使用DROP刪除數據庫同樣，您能夠使用DROP徹底刪除用戶：
DROP USER ‘demo’@‘localhost’;

要測試您的新用戶，請經過鍵入註銷
quit

並使用此命令在終端中從新登陸： mysql -u [username]-p