• export PATH=$PATH:/usr/local/mysql/bin/ 把mysql加入環境變量可以直接使用mysql命令，永久生效要把這條命令放到/etc/profile,並source /etc/profile
• 設置密碼

  [root@aminglinux-02 ~]# mysqladmin -uroot password ‘s5381561‘
  Warning: Using a password on the command line interface can be insecure.
  [root@aminglinux-02 ~]# mysql -uroot 
  ERROR 1045 (28000): Access denied for user ‘root‘@‘localhost‘ (using password: NO)
   
  

• 更改密碼

  [root@aminglinux-02 ~]# mysqladmin -uroot -p‘s5381561‘ password ‘123456‘
  Warning: Using a password on the command line interface can be insecure.
  [root@aminglinux-02 ~]# mysql -uroot -p‘123456‘
  mysql> 

• 忘記密碼時，進行密碼更改
  • 改配置文件

    [root@aminglinux-02 ~]# vim /etc/my.cnf
    [mysqld]
    skip-grant  #忽略授權
    [root@aminglinux-02 ~]# vim /etc/my.cnf
    [root@aminglinux-02 ~]# /etc/init.d/mysqld restart
    Shutting down MySQL.. SUCCESS! 
    Starting MySQL.. SUCCESS! 
    [root@aminglinux-02 ~]# mysql -uroot
    Welcome to the MySQL monitor.  Commands end with ; or \g.
     
    

  • 更改密碼

    [root@aminglinux-02 ~]# mysql -uroot
    Welcome to the MySQL monitor.  Commands end with ; or \g.
    mysql> use mysql;
    #切換mysql庫
    Database changed
    mysql> select * from user\G;
    #查看用戶的表信息，該表中存放的是用戶相關信息（密碼、授權…）
    #G選項的作用是使輸出信息有序顯示，不加該選項，顯示內容會很亂  
    mysql> select password from user;
    #查看用戶密碼，顯示結果Wie加密字符串！  
    mysql> update user set password=password(‘1234567‘) where user=‘root‘;
    Query OK, 4 rows affected (0.11 sec)
    Rows matched: 4  Changed: 4  Warnings: 0
    #將密碼更改為‘1234567’
    mysql> quit
    Bye
     
    

  • 恢復配置文件並重啟

    [root@aminglinux-02 ~]# vim /etc/my.cnf
    [root@aminglinux-02 ~]# /etc/init.d/mysqld restart
    Shutting down MySQL.. SUCCESS! 
    Starting MySQL. SUCCESS! 
    [root@aminglinux-02 ~]# mysql -uroot -p1234567
    Warning: Using a password on the command line interface can be insecure.

連接mysql

• 遠程連接

  [root@aminglinux-02 ~]# mysql -uroot -p1234567 -h127.0.0.1 -P3306
  Warning: Using a password on the command line interface can be insecure.

• 本地連接

  [root@aminglinux-02 ~]# mysql -uroot -p1234567 -S/tmp/mysql.sock
  Warning: Using a password on the command line interface can be insecure.

• 顯示所有數據庫,該方法使用於shell腳本中

  [root@aminglinux-02 ~]# mysql -uroot -p‘1234567‘ -e "show databases"
  Warning: Using a password on the command line interface can be insecure.
  +--------------------+
  | Database           |
  +--------------------+
  | information_schema |
  | mysql              |
  | performance_schema |
  | test               |
  +--------------------+

  mysql常用命令

• 查看庫信息
  • show databases; | 查詢所有數據庫
  • use db_name; | 切換庫
  • show tables; | 查看庫中的表
  • desc tb_name | 查看表裏的字段
  • show create table tb_name\G; | 查看建表語句
  • select user(); | 查看當前用戶
  • select database(); | 查看當前使用的數據庫
  • select * from user\G; | 查看所有用戶
• 編輯庫
  • create database db_name； | 創建庫
  • use db_name;create table tb_name | 在某庫下創建表
  • select version(); | 查看當前數據庫版本
  • show status; | 查看數據庫狀態
  • show variables; | 查看所有參數
  • show variables like ‘max_connet%‘ | 查看某參數,%為通配符
  • set global max_connect_errors=100; | 修改某參數 可以在my.cnf裏永久修改
  • show processlist; | 查看mysql進程隊列
  • show full processlist | 查看隊列詳細信息
  • drop database db_name | 刪除庫
• 代碼

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
+--------------------+
4 rows in set (0.00 sec)

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
mysql> show tables;
+---------------------------+
| Tables_in_mysql           |
+---------------------------+
| columns_priv              |
| db                        |
| event                     |
| func                      |
| time_zone                 |
| time_zone_leap_second     |
+---------------------------+
28 rows in set (0.00 sec)

mysql> desc time_zone;
+------------------+------------------+------+-----+---------+----------------+
| Field            | Type             | Null | Key | Default | Extra          |
+------------------+------------------+------+-----+---------+----------------+
| Time_zone_id     | int(10) unsigned | NO   | PRI | NULL    | auto_increment |
| Use_leap_seconds | enum(‘Y‘,‘N‘)    | NO   |     | N       |                |
+------------------+------------------+------+-----+---------+----------------+
2 rows in set (0.11 sec)

mysql> show create table time_zone\G;
#G=grep篩選文字內容，規律顯示出來
*************************** 1. row ***************************
       Table: time_zone
Create Table: CREATE TABLE `time_zone` (
  `Time_zone_id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `Use_leap_seconds` enum(‘Y‘,‘N‘) NOT NULL DEFAULT ‘N‘,
  PRIMARY KEY (`Time_zone_id`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COMMENT=‘Time zones‘
1 row in set (0.03 sec)

ERROR: 
No query specified

mysql> select user();
+----------------+
| user()         |
+----------------+
| root@localhost |
+----------------+
1 row in set (0.07 sec)

mysql> select database();
+------------+
| database() |
+------------+
| mysql      |
+------------+
1 row in set (0.00 sec)

mysql> select * from user\G;
創建庫：
mysql> create database db1;
Query OK, 1 row affected (0.02 sec)

創建表：
mysql> use db1;  
#先切換到指定庫下
Database changed
mysql> create table t1(`id` int(4),`name` char(40)) ENGINE=InnoDB DEFAULT CHARSET=utf8;
#括號中是定義字段及字段格式，使用反引號引起來
Query OK, 0 rows affected (1.51 sec)

mysql> select version();
+-----------+
| version() |
+-----------+
| 5.6.35    |
+-----------+
1 row in set (0.06 sec)

mysql> show status;
+-----------------------------------------------+-------------+
| Variable_name                                 | Value       |
+-----------------------------------------------+-------------+
| Aborted_clients                               | 0           |
| Aborted_connects                              | 0           |
+-----------------------------------------------+-------------+

mysql> show variables\G;

mysql> show variables like ‘max_connect%‘\G;
#like表示匹配；%是通配符

更改參數：
mysql> set global max_connect_errors=110;
Query OK, 0 rows affected (0.04 sec)
#在此只是臨時更改，如果要永久更改，需要編輯配置文件

查看隊列：
mysql> show processlist;
+----+------+-----------+------+---------+------+-------+------------------+
| Id | User | Host      | db   | Command | Time | State | Info             |
+----+------+-----------+------+---------+------+-------+------------------+
|  5 | root | localhost | db1  | Query   |    0 | init  | show processlist |
+----+------+-----------+------+---------+------+-------+------------------+
1 row in set (0.01 sec)

mysql> drop table t1;
Query OK, 0 rows affected (0.32 sec)

mysql> drop database db1;
Query OK, 0 rows affected (0.10 sec)

擴展

• mysql5.7 root密碼更改
• myisam 和innodb引擎對比
• mysql 配置詳解：
• mysql調優：
• 同學分享的親身mysql調優經歷：

mysql更改root密碼,連接mysql，常用操作