一、簡介
由MySQL AB公司開發，是最流行的開放源碼SQL數據庫管理系統，主要特點：
1、是一種數據庫管理系統
2、是一種關聯數據庫管理系統
3、是一種開放源碼軟件，且有大量可用的共享MySQL軟件
4、MySQL數據庫服務器具有快速、可靠和易於使用的特點
5、MySQL服務器工作在客戶端/服務器模式下，或嵌入式系統中
InnoDB存儲引擎將InnoDB表保存在一個表空間內，該表空間可由數個文件創建。這樣，表的大小就能超過單獨文件的最大容量。表空間可包括原始磁盤分區，從而使得很大的表成爲可能。表空間的最大容量爲64TB。
二、MySQL用戶賬號、權限管理
2.1. MySQL用戶賬號包括：用戶名@主機名
用戶名：16個字符以內
主機有以下幾種表現方式
主機名： mysql, www.magedu.com
IP地址: 172.16.90.111
網絡地址：172.16.0.0/255.255.0.0
通配符：%，_
%：任意字符 172.16.%.% ,%.magedu.com
_：任意一個 172.16_.%.%
2.2. 權限級別： 全局級別、 庫級別、 表級別、 列級別、 存儲過程 和存儲函數級別
全局級別：SELECT * FROM db\G; 查詢全局庫級別的權限
mysql> SELECT * FROM db \G
*************************** 1. row ***************************
Host: %
Db: test
User:
Select_priv: Y
Insert_priv: Y
Update_priv: Y
Delete_priv: Y
Create_priv: Y
Drop_priv: Y
Grant_priv: N
References_priv: Y
Index_priv: Y
Alter_priv: Y
Create_tmp_table_priv: Y
Lock_tables_priv: Y
Create_view_priv: Y
Show_view_priv: Y
Create_routine_priv: Y
Alter_routine_priv: N
Execute_priv: N
Event_priv: Y
Trigger_priv: Y
**************************************************************************
CREATE USER username@host [IDENTIFIED BY 'password'] 創建用戶
DROP USER 'username'@'host'; 刪除用戶
RENAME USER old_name TO new_name; 重命名用戶
SHOW GRANTS FOR 'username'@'host'; 查看用戶權限列表
FLUSH PRIVILEGES ; 刷新權限列表
GRANT PRIVILEGES ON [object_type] db.* TO 'username'@'host'; 給用戶增加權限
REVOKE SELECT ON db.* FROM 'username'@'host'; 取消用戶的SELECT權限
2.3. 權限對應的作用範圍明細：
2.4. 創建用戶及權限：
2.4.1. 創建用戶，並通過IDENTIFIED BY 'password'，設定密碼
CREATE USER username@host [IDENTIFIED BY 'password']
Usage:
mysql> CREATE USER test@localhost IDENTIFIED BY 'test'; #創建用戶test本地數據庫賬號，密碼test。
Query OK, 0 rows affected (0.00 sec)
mysql> FLUSH PRIVILEGES ; #刷新權限列表
Query OK, 0 rows affected (0.00 sec)
mysql> SHOW GRANTS FOR test@localhost\G; #查看數據庫賬戶test@localhost的權限列表
*************************** 1. row ***************************
Grants for test@localhost: GRANT USAGE ON *.* TO 'test'@'localhost' IDENTIFIED BY PASSWORD '*94BDCEBE19083CE2A1F959FD02F964C7AF4CFC29'
1 row in set (0.00 sec)
2.4.2. 測試登錄
重新打開另一個客戶端，登錄以test賬號登錄mysql
[root@lamp ~]# mysql -utest -p #登錄mysql數據庫以test用戶，輸入用戶密碼
mysql> SHOW DATABASES; #登錄成功，查看該賬號下的數據庫
+--------------------+
| Database |
+--------------------+
| information_schema |
| test |
+--------------------+
2 rows in set (0.00 sec)
2.4.3. 權限設定GRANT
GRANT PRIVILEGES ON [object_type] db.* TO 'username'@'host';
#指定權限PRIVILEGES
ON指定對象名稱db.*
object_type指定對象類型:
TABLE 表
| FUNCTION 函數
| PROCEDURE
TO username@host 指定用戶。
with_option:
GRANT OPTION
| MAX_QUERIES_PER_HOUR count
| MAX_UPDATES_PER_HOUR count
| MAX_CONNECTIONS_PER_HOUR count
| MAX_USER_CONNECTIONS count
object_type對象類型有：TABLE（表） FUNCTION（函數） PROCEDURE(程序、庫)
Usage：GRANT EXECUTE ON FUNCTION db.abc TO 'username'@'host'; #授權給username@host用戶,對
db數據庫的abc函數有執行權限。
GRANT UPDATE(Age) ON db.testtb TO 'username'@'host'; #授權給username@host用戶對db數據庫的，testtb表的Age字段具有UPDATE權限。
2.4.3.1.測試開通創建庫權限
A連接：
mysql> GRANT CREATE ON test01.* TO 'test'@'%';
Query OK, 0 rows affected (0.01 sec)
B連接：（A連接命令執行前）
mysql> CREATE DATABASE test01;
ERROR 1007 (HY000): Can't create database 'test'; database exists
B連接：（A連接命令執行後）
mysql> CREATE DATABASE test01;
Query OK, 1 row affected (0.00 sec)
mysql> use test01
Database changed
mysql> CREATE TABLE testdb (ID INT UNSINED AUTO_INCREMENT NOT NULL,Name CHAR(20),PRIMARY KEY (ID));
Query OK, 0 rows affected (0.02 sec)
2.4.3.2.測試開通創建表權限，權限設定後需重連
A連接：
mysql> GRANT INSERT ON test01.* TO 'test'@'%';
Query OK, 0 rows affected (0.01 sec)
mysql> GRANT SELECT ON test01.* TO 'test'@'%';
Query OK, 0 rows affected (0.01 sec)
mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.01 sec)
mysql> SHOW GRANTS FOR 'test'@'%'; #查看權限正常
+----------------------------------------------------------+
| Grants for test@% |
+----------------------------------------------------------+
| GRANT USAGE ON *.* TO 'test'@'%' |
| GRANT CREATE ON `test`.* TO 'test'@'%' |
| GRANT SELECT, INSERT, CREATE ON `test01`.* TO 'test'@'%' |
+----------------------------------------------------------+
3 rows in set (0.00 sec)
[root@lamp ~]# tail /mydata/data/lamp.err #查看日誌正常
170612 9:31:34 InnoDB: Completed initialization of buffer pool
170612 9:31:34 InnoDB: highest supported file format is Barracuda.
170612 9:31:35 InnoDB: Waiting for the background threads to start
170612 9:31:36 InnoDB: 1.1.8 started; log sequence number 5241255
170612 9:31:36 [Note] Server hostname (bind-address): '0.0.0.0'; port: 3306
170612 9:31:36 [Note] - '0.0.0.0' resolves to '0.0.0.0';
170612 9:31:36 [Note] Server socket created on IP: '0.0.0.0'.
170612 9:31:36 [Note] Event Scheduler: Loaded 0 events
170612 9:31:36 [Note] /usr/local/mysql/bin/mysqld: ready for connections.
Version: '5.5.28-log' socket: '/tmp/mysql.sock' port: 3306 Source distribution
B連接：（A連接命令執行前）
mysql> USE test01
Database changed
mysql> INSERT INTO testdb (Name) VALUES ('TOM');
ERROR 1142 (42000): INSERT command denied to user 'test'@'localhost' for table 'testtb'
B連接：（A連接命令執行且重新連接會話後）
mysql> use test01
Database changed
mysql> INSERT INTO testdb (Name) VALUES ('TOM');
Query OK, 1 row affected (0.01 sec)
2.4.3.3.測試開通新增表中字段的權限，權限設定後需重連
A連接：
mysql> GRANT ALTER ON test01.* TO 'test'@'%';
Query OK, 0 rows affected (0.00 sec)
mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)
B連接：（A連接命令執行前）
mysql> ALTER TABLE testdb ADD Age TINYINT UNSIGNED;
ERROR 1142 (42000): ALTER command denied to user 'test'@'localhost' for table 'testdb'
B連接：（A連接命令執行且重新連接會話後）
mysql> use test01;
Database changed
mysql> ALTER TABLE testdb ADD Age TINYINT UNSIGNED;
Query OK, 1 row affected (0.03 sec)
Records: 1 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM testdb;
+----+------+------+
| ID | Name | Age |
+----+------+------+
| 1 | TOM | NULL |
+----+------+------+
1 row in set (0.00 sec)
2.4.3.4.測試開通新增表中字段的權限，權限設定後需重連
A連接：
mysql> GRANT UPDATE(Age) ON test01.testdb TO 'test'@'%';
Query OK, 0 rows affected (0.00 sec)
mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)
mysql> SHOW GRANTS FOR 'test'@'%';
+-----------------------------------------------------------------+
| Grants for test@% |
+-----------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'test'@'%' |
| GRANT CREATE ON `test`.* TO 'test'@'%' |
| GRANT SELECT, INSERT, CREATE, ALTER ON `test01`.* TO 'test'@'%' |
| GRANT UPDATE (Age) ON `test01`.`testdb` TO 'test'@'%' |
+-----------------------------------------------------------------+
4 rows in set (0.00 sec)
B連接：（A連接命令執行且重新連接會話後）
mysql> use test01;
mysql> UPDATE testdb SET Age=30 WHERE ID=1;
Query OK, 1 row affected (0.01 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> SELECT * FROM testdb;
+----+------+------+
| ID | Name | Age |
+----+------+------+
| 1 | TOM | 30 |
+----+------+------+
1 row in set (0.00 sec)
mysql> UPDATE testdb SET Name='Jack' WHERE ID=1; #只有更新Age的權限，所以出錯
ERROR 1143 (42000): UPDATE command denied to user 'test'@'localhost' for column 'Name' in table 'testdb'
2.4.3.5.測試開通全局的權限，權限設定後需重連 XXX測試失敗
A連接：
mysql> SET GLOBAL tx_isolation='READ-UNCOMMITTED';
ERROR 1227 (42000): Access denied; you need (at least one of) the SUPER privilege(s) for this operation
mysql> show grants for 'test'@'%';
+-----------------------------------------------------------------+
| Grants for test@% |
+-----------------------------------------------------------------+
| GRANT SUPER ON *.* TO 'test'@'%' |
| GRANT CREATE ON `test`.* TO 'test'@'%' |
| GRANT SELECT, INSERT, CREATE, ALTER ON `test01`.* TO 'test'@'%' |
| GRANT UPDATE (Age) ON `test01`.`testdb` TO 'test'@'%' |
+-----------------------------------------------------------------+
4 rows in set (0.00 sec)
B連接：（A連接命令執行且重新連接會話後）
mysql> use test01;
mysql> set GLOBAL tx_isolation = 'READ-UNCOMMITTED';
ERROR 1227 (42000): Access denied; you need (at least one of) the SUPER privilege(s) for this operation
mysql>
2.4.3.6.測試撤銷授權
mysql> help revoke
Name: 'REVOKE'
Syntax:
REVOKE
priv_type [(column_list)]
[, priv_type [(column_list)]] ...
ON [object_type] priv_level
FROM user [, user] ...
REVOKE ALL PRIVILEGES, GRANT OPTION
FROM user [, user] ...
REVOKE PROXY ON user
FROM user [, user] ...
mysql> show grants for 'test'@'%';
+-----------------------------------------------------------------+
| Grants for test@% |
+-----------------------------------------------------------------+
| GRANT SUPER ON *.* TO 'test'@'%' |
| GRANT CREATE ON `test`.* TO 'test'@'%' |
| GRANT SELECT, INSERT, CREATE, ALTER ON `test01`.* TO 'test'@'%' |
| GRANT UPDATE (Age) ON `test01`.`testdb` TO 'test'@'%' |
+-----------------------------------------------------------------+
4 rows in set (0.00 sec)
mysql> revoke SELECT ON test.* FROM 'test'@'%';
Query OK, 0 rows affected (0.00 sec)
mysql> show grants for 'test'@'%';
+-----------------------------------------------------------------+
| Grants for test@% |
+-----------------------------------------------------------------+
| GRANT SUPER ON *.* TO 'test'@'%' |
| GRANT CREATE ON `test`.* TO 'test'@'%' |
| GRANT SELECT, INSERT, CREATE, ALTER ON `test01`.* TO 'test'@'%' |
| GRANT UPDATE (Age) ON `test01`.`testdb` TO 'test'@'%' |
+-----------------------------------------------------------------+
4 rows in set (0.00 sec)
2.4.3.7.測試開通SSL連接的權限，權限設定後需重連
2.4.3.8.測試開通其它的權限，權限設定後需重連
mysql> help drop user #刪除用戶
Name: 'DROP USER'
Syntax:
DROP USER user [, user] ...
mysql> help rename user #用戶重命名
Name: 'RENAME USER'
Syntax:
RENAME USER old_user TO new_user
[, old_user TO new_user] ...
2.5. MySQL數據庫ROOT用戶密碼忘記解決方案步驟：
2.3.1. 先關閉mysqld進程，並修改配置文件/etc/my.cnf
[root@lamp ~]# service mysqld stop #先停止mysqld進程
Shutting down MySQL.. [ OK ]
[root@lamp ~]# vim /etc/init.d/mysqld #修改mysqld的啓動腳本，修改內容如下紅色框內
查找start: /start
新增跳過權限表及禁止網絡登錄： --skip-grant-tables --skip-networking
2.3.2. 啓動mysqld服務，並登入修改mysql.user中的密碼
[root@lamp ~]# service mysqld start #啓動mysqld進程
Starting MySQL.. [ OK ]
[root@lamp ~]# mysql #此時登錄mysql即可不需要用戶名和密碼
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.5.28-log Source distribution
Copyright (c) 2000, 2012, 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> USE mysql
Database changed
mysql> SELECT User,Host,Password FROM user; #查詢user表的三個字段，是需要密碼登錄的
+------+-----------+-------------------------------------------+
| User | Host | Password |
+------+-----------+-------------------------------------------+
| root | localhost | *A198E6EEE923DA319BBF86C99624479A198E6EEE9 |
| root | lamp | *A198E6EEE9823DA319BBF86C99624479A198E6EEE9 |
| root | 127.0.0.1 | *A198E6EEE9DA319BBF86C99624479A198E6EEE9 |
| root | ::1 | *A198E6EEE93DA319BBF86C99624479A198E6EEE9 |
| test | localhost | *94BDCEBE19083CE2A1F959FD02F964C7AF4CFC29 |
+------+-----------+-------------------------------------------+
5 rows in set (0.00 sec)
mysql> UPDATE user SET Password=PASSWORD('redhat') WHERE User='root';
#此時由於跳過了grant權限列表，所以只能通過修改user表的Password字段的值來修改用戶密碼。
Query OK, 0 rows affected (0.00 sec)
Rows matched: 4 Changed: 0 Warnings: 0
mysql> SELECT User,Host,Password FROM user; #查詢user表的三個字段，是需要密碼登錄的
+------+-----------+-------------------------------------------+
| User | Host | Password |
+------+-----------+-------------------------------------------+
| root | localhost | *84BB5DF4823DA319BBF86C99624479A198E6EEE9 |
| root | lamp | *84BB5DF4823DA319BBF86C99624479A198E6EEE9 |
| root | 127.0.0.1 | *84BB5DF4823DA319BBF86C99624479A198E6EEE9 |
| root | ::1 | *84BB5DF4823DA319BBF86C99624479A198E6EEE9 |
| test | localhost | *94BDCEBE19083CE2A1F959FD02F964C7AF4CFC29 |
+------+-----------+-------------------------------------------+
5 rows in set (0.00 sec)
mysql>\q
2.3.3. 關閉mysqld服務，並登入刪除之前增加的安全啓動參數
[root@lamp ~]# service mysqld stop #停止mysqld進程
Shutting down MySQL. [ OK ]
[root@lamp ~]# vim /etc/init.d/mysqld #修改啓動腳本，把之前修改的內容去掉後保存退出
2.3.4. 啓動mysqld服務，並使用修改後的密碼登錄
[root@lamp ~]# service mysqld start #啓動mysqld進程
Starting MySQL.. [ OK ]
[root@lamp ~]# mysql #此時直接登錄mysql提示輸入用戶及密碼
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
[root@lamp ~]# mysql -uroot -p #指定通過root賬號登錄 -p指定需要輸入密碼登錄
Enter password:
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