设置、更改root用户密码
首次使用mysql会提示‘该命令不在’,原因是还没有将该命令加入环境变量,如果要使用该命令,需要使用其绝对路径:/usr/local/mysql/bin/mysql,为了方便,先将其加入系统环境变量。
[[email protected] ~]# export PATH=$PATH:/usr/local/mysql/bin/mysql
重启系统后该变量会失效,若要永久生效,需要将其加入环境变量配置文件:
[[email protected] ~]# vim /etc/profile
......
export PATH=$PATH:/usr/local/mysql/bin/
刷新配置:
[[email protected] ~]# source /etc/profile
- 设置密码
首次登陆mysql,root用户没有密码,直接登陆
[[email protected] ~]# mysql -uroot
//-u指定用户登录
Welcome to the MySQL monitor. Commands end with ; or \g.
......
mysql>quit
Bye
// quit命令可以退出mysql。设置密码:
[[email protected] ~]# mysqladmin -uroot password ‘123456‘
Warning: Using a password on the command line interface can be insecure.
// 这里并没有报错,只是提示说密码在命令行显示出来了不×××全。不使用密码登录:
[[email protected] ~]# mysql -uroot
ERROR 1045 (28000): Access denied for user ‘root‘@‘localhost‘ (using password: NO)
// 提示登录被拒绝,需要密码。使用密码登录:
[[email protected] ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
......
// -p参数,使用密码登录。可以将密码接在-p后。也可以不在-p后输入密码,根据后面的提示信息输入,这个方法不会暴露用户密码,更安全。
注意: 在没设置root密码时使用-p参数登录mysql,会提示输入密码,这是直接回车就行。
- 更改密码
当知道用户密码时,进行密码更改:
[[email protected] ~]# mysqladmin -uroot -p‘123456‘ password ‘654321‘
Warning: Using a password on the command line interface can be insecure.
// 警告密码在命令行输入,不安全。但是密码已经修改成功!使用旧密码登录:
[[email protected] ~]# mysql -uroot -p123456
Warning: Using a password on the command line interface can be insecure.
// 警告密码在命令行输入,不安全。
ERROR 1045 (28000): Access denied for user ‘root‘@‘localhost‘ (using password: YES)
// 提示登录信息验证失败,密码错误!使用新密码登录
[[email protected] ~]# mysql -uroot -p654321
Warning: Using a password on the command line interface can be insecure.
// 警告密码在命令行输入,不安全。
Welcome to the MySQL monitor. Commands end with ; or \g.
......
mysql>
// 使用新密码登录成功! - 密码重置
在不记得root密码时使用,重置密码。
编辑配置文件:
[[email protected] ~]# vim /etc/my.cnf
[mysqld]
skip-grant // 忽略授权!
......
// 在mysqld模块下加入代码:skip-grant重启mysql服务:
[[email protected] ~]# /etc/init.d/mysqld restart
Shutting down MySQL.. SUCCESS!
Starting MySQL.. SUCCESS!
注意: 完成上面操作之后登录mysql就不需要密码了。
登录mysql:
[[email protected] ~]# mysql -uroot
Welcome to the MySQL monitor. Commands end with ; or \g.
......
mysql>
// 不使用-p参数直接登录。
切换到mysql库:
mysql> use mysql; // 切换到mysql库
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\G;
// 查看用户的表信息,该表中存放的是用户相关信息(密码、授权…)
// G选项的作用是使输出信息有序显示,不加该选项,显示内容会很乱
mysql> select password from user;
// 查看用户密码,显示结果Wie加密字符串!
重置密码:
mysql> update user set password=password(‘112233‘) where user=‘root‘;
Query OK, 4 rows affected (0.11 sec)
Rows matched: 4 Changed: 4 Warnings: 0
// 将密码更改为‘112233’
恢复配置文件:
[[email protected] ~]# vim /etc/my.cnf
// 将之前加入skip-grant那行注释掉
重启mysql服务:
[[email protected] ~]# /etc/init.d/mysqld restart
Shutting down MySQL.. SUCCESS!
Starting MySQL. SUCCESS!
登录:
[[email protected] ~]# mysql -uroot -p‘112233‘
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
......
mysql>
重置密码步骤: vim /etc/my.cnf-->添加skip-grant-->mysql restart-->登录-->use mysql-->update user set password=...-->vim /etc/my.cnf-->删除skip-grant-->mysql restart。
连接mysql
- 远程连接
使用IP和端口号连接
[[email protected] ~]# mysql -uroot -p‘112233‘ -h127.0.0.1 -P3306
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
......
mysql>// -h=host,指定IP,-P=port,指定端口号
- 本地连接
直接可以直接连接或使用socket连接。
使用socket链接:
[[email protected] ~]# mysql -uroot -p‘112233‘ -S/tmp/mysql.sock
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
......
mysql>// -S=socket,指定socket。此方法只适用于本地连接。和直接mysql连接一样。
- 连接数据后显示所有数据库
[[email protected] ~]# mysql -uroot -p‘112233‘ -e "show databases"
Warning: Using a password on the command line interface can be insecure.
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
+--------------------+-e 参数后可以跟一条mysql语句。
// 该方法常用于shell脚本中。
Mysql 常用命令
查看有哪些数据库:
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
+--------------------+
4 rows in set (0.00 sec)
切换到mysql库:
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>
查看库里的表:
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)
查看表里面的字段:
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 | |
......
+------------------------+-----------------------------------+------+-----+-----------------------+-------+
43 rows in set (0.00 sec)
查看表是怎么创建的
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‘,
......
// \G 是让结果竖排显示;
查看当前登录的用户:
mysql> select user();
+----------------+
| user() |
+----------------+
| [email protected] |
+----------------+
1 row in set (0.00 sec)
查看当前所在的库:
mysql> select database();
+------------+
| database() |
+------------+
| mysql |
+------------+
1 row in set (0.00 sec)
创建库:
mysql> create database db1;
Query OK, 1 row affected (0.00 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| db1 |
| mysql |
| performance_schema |
| test |
+--------------------+
5 rows in set (0.00 sec)
mysql> use db1 //切换到db1库
Database changed
创建表:
mysql> use db1;
// 先切换到指定库下
Database changed
mysql> create table t1(`id` int(4),`name` char(40));
// 括号中是定义字段及字段格式,使用反引号引起来
Query OK, 0 rows affected (1.51 sec)
// drop table t1,可以删除表。
查看当前数据库的版本:
mysql> select version();
+-----------+
| version() |
+-----------+
| 5.6.35 |
+-----------+
1 row in set (0.00 sec)
// 数据库版本:5.6.35
查看数据库状态:
mysql> show status;
+-----------------------------------------------+-------------+
| Variable_name | Value |
+-----------------------------------------------+-------------+
| Aborted_clients | 0 |
| Aborted_connects | 0 |
+-----------------------------------------------+-------------+
查看所有参数:
mysql> show variables\G; //查看所有参数
查看指定参数
mysql> show variables like ‘max_connect%‘\G;
// like表示匹配;%是通配符
更改参数:
mysql> set global max_connect_errors=110;
Query OK, 0 rows affected (0.04 sec)
#在此只是临时更改,如果要永久更改,需要编辑配置文件/etc/my.cnf
查看队列:
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)
完整显示:
mysql> show full processlist;
+----+------+-----------+------+---------+------+-------+-----------------------+
| Id | User | Host | db | Command | Time | State | Info |
+----+------+-----------+------+---------+------+-------+-----------------------+
| 6 | root | localhost | db1 | Query | 0 | init | show full processlist |
+----+------+-----------+------+---------+------+-------+-----------------------+
1 row in set (0.00 sec)
在mysql中 drop 后跟库或者表名,可以删除库或者表。
可以使用 ctrl+l 清屏
mysql的历史命令在.mysql_history 文件中。
原文地址:http://blog.51cto.com/754599082/2060315