設置mysql用戶密碼（5.6/5.7）、遠程連接數據庫、常用命令

設置mysql用戶密碼

首先，直接使用mysql命令是會有提示“命令不存在”，原因是該命令沒有加入系統環境變量。

暫時將其加入環境變量中：

[root@shuai-01 ~]# export PATH=$PATH:/usr/local/mysql/bin/

這時，只是暫時將其加入環境變量中，關機後就使用不了了。要想使其永久生效，要將這條命令寫入/etc/profile中

[root@shuai-01 ~]# vim /etc/profile


export PATH=$PATH:/usr/local/mysql/bin/

保存退出後，重啓

[root@shuai-01 ~]# source /etc/profile

這時就可以使用mysql命令直接登陸了。

[root@shuai-01 ~]# mysql -uroot -p
Enter password: 

設置mysql密碼爲000000

[root@shuai-01 ~]# mysqladmin -uroot password '000000'

登錄

[root@shuai-01 ~]# mysql -uroot -p000000

修改和重置密碼

修改密碼：
將root密碼修改爲shuai
[root@localhost ~]# mysqladmin -uroot -p000000 password 'shuai'

新密碼登錄：

[root@shuai-01 ~]# mysql -uroot -pshuai
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.6.36 MySQL Community Server (GPL)

Copyright (c) 2000, 2017, 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> quit
Bye


---------------------------------------------


重置密碼

1. 編輯my.cnf配置文件
[root@localhost ~]# vim /etc/my.cnf
[mysqld]下添加 skip-grant

 
重啓mysql服務

[root@localhost ~]# /etc/init.d/mysqld restart
這時可以直接登陸mysql，不用密碼。

2. 利用mysql庫中的user表修改密碼

[root@localhost ~]# mysql -uroot
use mysql
select * from user;
update user set password=password('重置後的密碼') where user='root';

將root密碼改爲111111

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> select * from user;
mysql> update user set password=password('111111') where user='root';
Query OK, 4 rows affected (0.04 sec)
Rows matched: 4  Changed: 4  Warnings: 0

退出mysql

進入/etc/profile中取消skip-grant

重啓mysql服務。

[root@localhost ~]# /etc/init.d/mysqld restart

mysql5.7 root密碼更改 http://www.apelearn.com/bbs/thread-7289-1-1.html

連接Mysql

mysql的幾種連接方式

1. 直接輸入用戶名和密碼。適用於本機用戶連接本機mysql

mysql -uroot -p123456

2. 通過ip和端口連接mysql，適用於本機用戶連接本機mysql或者本機用戶連接遠端mysql
mysql -uroot -p123456 -h127.0.0.1 -P3306

[root@shuai-01 ~]# mysql -uroot -p111111 -h127.0.0.1 -P3306

3. 通過sock套接字文件連接mysql，適用於本機用戶連接本機mysql（只適合本機）
mysql -uroot -p123456 -S/tmp/mysql.sock
[root@shuai-01 ~]# mysql -uroot -p111111 -S/tmp/mysql.sock


4. 連接mysql的同時執行mysql語句
mysql -uroot -p123456 -e “show databases”
顯示所有的數據庫
    [root@shuai-01 ~]# mysql -uroot -p111111 -e "show databases"
Warning: Using a password on the command line interface can be insecure.
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
+--------------------+

使用與shell腳本

Mysql常用命令

mysql命令語句完了一定要加’；’ 
mysql常用命令

查詢庫 show databases;
mysql> show databases
    -> ;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
+--------------------+
4 rows in set (0.10 sec)

切換庫 use mysql;

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

查看庫裏的表 show tables;

mysql> show tables;
+---------------------------+
| Tables_in_mysql           |
+---------------------------+
| columns_priv              |
| db                        |
| event                     |
| func                      |
| general_log               |
| help_category             |
| help_keyword              |
| help_relation             |
| help_topic                |
| innodb_index_stats        |
| innodb_table_stats        |
| ndb_binlog_index          |
| plugin                    |
| proc                      |
| procs_priv                |
| proxies_priv              |
| servers                   |
| slave_master_info         |
| slave_relay_log_info      |
| slave_worker_info         |
| slow_log                  |
| tables_priv               |
| time_zone                 |
| time_zone_leap_second     |
| time_zone_name            |
| time_zone_transition      |
| time_zone_transition_type |
| user                      |
+---------------------------+
28 rows in set (0.00 sec)

查看錶裏的字段 desc tb_name; 
查看user表的字段

mysql> desc user;
+------------------------+-----------------------------------+------+-----+-----------------------+-------+
| Field                  | Type                              | Null | Key | Default               | Extra |
+------------------------+-----------------------------------+------+-----+-----------------------+-------+
| Host                   | char(60)                          | NO   | PRI |                       |       |
| User                   | char(16)                          | NO   | PRI |                       |       |
| Password               | char(41)                          | NO   |     |                       |       |
| Select_priv            | enum('N','Y')                     | NO   |     | N                     |       |
| Insert_priv            | enum('N','Y')                     | NO   |     | N                     |       |
| Update_priv            | enum('N','Y')                     | NO   |     | N                     |       |
| Delete_priv            | enum('N','Y')                     | NO   |     | N                     |       |
| Create_priv            | enum('N','Y')                     | NO   |     | N                     |       |
| Drop_priv              | enum('N','Y')                     | NO   |     | N                     |       |
| Reload_priv            | enum('N','Y')                     | NO   |     | N                     |       |
| Shutdown_priv          | enum('N','Y')                     | NO   |     | N                     |       |
| Process_priv           | enum('N','Y')                     | NO   |     | N                     |       |
| File_priv              | enum('N','Y')                     | NO   |     | N                     |       |
| Grant_priv             | enum('N','Y')                     | NO   |     | N                     |       |
| References_priv        | enum('N','Y')                     | NO   |     | N                     |       |
| Index_priv             | enum('N','Y')                     | NO   |     | N                     |       |
| Alter_priv             | enum('N','Y')                     | NO   |     | N                     |       |
| Show_db_priv           | enum('N','Y')                     | NO   |     | N                     |       |
| Super_priv             | enum('N','Y')                     | NO   |     | N                     |       |
| Create_tmp_table_priv  | enum('N','Y')                     | NO   |     | N                     |       |
| Lock_tables_priv       | enum('N','Y')                     | NO   |     | N                     |       |
| Execute_priv           | enum('N','Y')                     | NO   |     | N                     |       |
| Repl_slave_priv        | enum('N','Y')                     | NO   |     | N                     |       |
| Repl_client_priv       | enum('N','Y')                     | NO   |     | N                     |       |
| Create_view_priv       | enum('N','Y')                     | NO   |     | N                     |       |
| Show_view_priv         | enum('N','Y')                     | NO   |     | N                     |       |
| Create_routine_priv    | enum('N','Y')                     | NO   |     | N                     |       |
| Alter_routine_priv     | enum('N','Y')                     | NO   |     | N                     |       |
| Create_user_priv       | enum('N','Y')                     | NO   |     | N                     |       |
| Event_priv             | enum('N','Y')                     | NO   |     | N                     |       |
| Trigger_priv           | enum('N','Y')                     | NO   |     | N                     |       |
| Create_tablespace_priv | enum('N','Y')                     | NO   |     | N                     |       |
| ssl_type               | enum('','ANY','X509','SPECIFIED') | NO   |     |                       |       |
| ssl_cipher             | blob                              | NO   |     | NULL                  |       |
| x509_issuer            | blob                              | NO   |     | NULL                  |       |
| x509_subject           | blob                              | NO   |     | NULL                  |       |
| max_questions          | int(11) unsigned                  | NO   |     | 0                     |       |
| max_updates            | int(11) unsigned                  | NO   |     | 0                     |       |
| max_connections        | int(11) unsigned                  | NO   |     | 0                     |       |
| max_user_connections   | int(11) unsigned                  | NO   |     | 0                     |       |
| plugin                 | char(64)                          | YES  |     | mysql_native_password |       |
| authentication_string  | text                              | YES  |     | NULL                  |       |
| password_expired       | enum('N','Y')                     | NO   |     | N                     |       |
+------------------------+-----------------------------------+------+-----+-----------------------+-------+
43 rows in set (0.14 sec)

查看建表語句 show create table tb_name\G; 
\G是將信息豎列顯示

mysql> show create table user\G;
*************************** 1. row ***************************
       Table: user
Create Table: CREATE TABLE `user` (
  `Host` char(60) COLLATE utf8_bin NOT NULL DEFAULT '',
  `User` char(16) COLLATE utf8_bin NOT NULL DEFAULT '',
  `Password` char(41) CHARACTER SET latin1 COLLATE latin1_bin NOT NULL DEFAULT '',
  `Select_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Insert_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Update_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Delete_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Create_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Drop_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Reload_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Shutdown_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Process_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `File_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Grant_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `References_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Index_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Alter_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Show_db_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Super_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Create_tmp_table_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Lock_tables_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Execute_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Repl_slave_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Repl_client_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Create_view_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Show_view_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Create_routine_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Alter_routine_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Create_user_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Event_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Trigger_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `Create_tablespace_priv` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  `ssl_type` enum('','ANY','X509','SPECIFIED') CHARACTER SET utf8 NOT NULL DEFAULT '',
  `ssl_cipher` blob NOT NULL,
  `x509_issuer` blob NOT NULL,
  `x509_subject` blob NOT NULL,
  `max_questions` int(11) unsigned NOT NULL DEFAULT '0',
  `max_updates` int(11) unsigned NOT NULL DEFAULT '0',
  `max_connections` int(11) unsigned NOT NULL DEFAULT '0',
  `max_user_connections` int(11) unsigned NOT NULL DEFAULT '0',
  `plugin` char(64) COLLATE utf8_bin DEFAULT 'mysql_native_password',
  `authentication_string` text COLLATE utf8_bin,
  `password_expired` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
  PRIMARY KEY (`Host`,`User`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_bin COMMENT='Users and global privileges'
1 row in set (0.08 sec)

查看當前用戶 select user();

mysql> select user();
+----------------+
| user()         |
+----------------+
| root@localhost |
+----------------+
1 row in set (0.30 sec)

記錄mysql命令歷史：

[root@shuai-01 ~]# less .mysql_history
use\040mysql
select\040*\040from\040user
;
show\040databases
;
use\040mysql
use\040mysql;
show\040tables;
desc\040user;
show\040create\040table\040user\134G;
select\040user();
.mysql_history (END)

查看當前使用的數據庫 select databsase();

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

創建庫 create database db1;

mysql> create database db1;
Query OK, 1 row affected (0.15 sec)

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| db1                |
| mysql              |
| performance_schema |
| test               |
+--------------------+
5 rows in set (0.00 sec)

創建表 use db1; create table t1(id int(4), namechar(40)); 
在數據庫中，表在庫中。

在db1庫中創建t1表；

mysql> use db1
Database changed
mysql> create table t1(`id` int(4),`name` char(20));
Query OK, 0 rows affected (0.84 sec)

mysql> show create table t1\G;
*************************** 1. row ***************************
       Table: t1
Create Table: CREATE TABLE `t1` (
  `id` int(4) DEFAULT NULL,
  `name` char(20) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1
1 row in set (0.06 sec)

ERROR: 
No query specified

或者

mysql> create table t1(`id` int(4),`name` char(20)) ENGINE=InnoDB DEFAULT CHARSET=utf8;
Query OK, 0 rows affected (0.12 sec)

刪除一個表（t1）

mysql> drop table t1;
Query OK, 0 rows affected (0.17 sec)
mysql> show tables;
Empty set (0.01 sec)

查看當前數據庫版本 select version();

mysql> select version();
+-----------+
| version() |
+-----------+
| 5.6.36    |
+-----------+
1 row in set (0.07 sec)

查看數據庫狀態 show status;列出常用的數據

查看各參數 
show variables; 
show variables like ‘max_connect%’; 
%可以通配

修改參數 set global max_connect_errors=1000;

查看隊列，查看mysql正在執行的操作

 show processlist; 
 show full processlist;

myisam 和innodb引擎對比 http://www.pureweber.com/article/myisam-vs-innodb/ 
mysql 配置詳解： http://blog.linuxeye.com/379.html 
mysql調優： http://www.aminglinux.com/bbs/thread-5758-1-1.html 
同學分享的親身mysql調優經歷： http://www.apelearn.com/bbs/thread-11281-1-1.html