Mysql入门基础命令
Posted Wolf_Dreams
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一、mysql基本操作
1.1 查询当前数据库
mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | dev | | guohua | | jumpserver | | mysql | | oldboy | | oldgirl | | performance_schema | | spdb | | wordpress | +--------------------+ 10 rows in set (0.25 sec)
1.2 查询特定库的表
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 | | 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)
1.3 查看特定表的全部字段
mysql> desc db;
+-----------------------+---------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------------------+---------------+------+-----+---------+-------+
| Host | char(60) | NO | PRI | | |
| Db | char(64) | NO | PRI | | |
| User | char(16) | NO | PRI | | |
| 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 | |
| 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 | |
| Create_tmp_table_priv | enum(‘N‘,‘Y‘) | NO | | N | |
| Lock_tables_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 | |
| Execute_priv | enum(‘N‘,‘Y‘) | NO | | N | |
| Event_priv | enum(‘N‘,‘Y‘) | NO | | N | |
| Trigger_priv | enum(‘N‘,‘Y‘) | NO | | N | |
+-----------------------+---------------+------+-----+---------+-------+
22 rows in set (0.01 sec)
#使用如下命令将建表语句全部列出来
mysql> show create table dbG;
*************************** 1. row ***************************
Table: db
Create Table: CREATE TABLE `db` (
`Host` char(60) COLLATE utf8_bin NOT NULL DEFAULT ‘‘,
`Db` char(64) COLLATE utf8_bin NOT NULL DEFAULT ‘‘,
`User` char(16) COLLATE utf8_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‘,
`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‘,
`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‘,
`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‘,
`Execute_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‘,
PRIMARY KEY (`Host`,`Db`,`User`),
KEY `User` (`User`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_bin COMMENT=‘Database privileges‘
1 row in set (0.00 sec)
1.4 查看当前登录的用户
mysql> select user(); +----------------+ | user() | +----------------+ | [email protected] | +----------------+ 1 row in set (0.00 sec)
1.5 查看当前正在使用的数据库
mysql> select database(); +------------+ | database() | +------------+ | mysql | +------------+ 1 row in set (0.00 sec)
1.6 创建一个新库
mysql> create database zabbix; Query OK, 1 row affected (0.38 sec)
1.7 创建一个新表
mysql> create table user(id int(4),name char(40),tel int(11));
Query OK, 0 rows affected (0.19 sec)
mysql> show create table userG
*************************** 1. row ***************************
Table: user
Create Table: CREATE TABLE `user` (
`id` int(4) DEFAULT NULL,
`name` char(40) DEFAULT NULL,
`tel` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1
1 row in set (0.00 sec)
1.8 查看当前mysql数据版本
mysql> select version(); +------------+ | version() | +------------+ | 5.6.40-log | +------------+ 1 row in set (0.00 sec)
1.9 查看Mysql当前状态
mysql> show status; +-----------------------------------------------+-------------+ | Variable_name | Value | +-----------------------------------------------+-------------+ | Aborted_clients | 0 | | Aborted_connects | 14 | | Binlog_cache_disk_use | 0 | | Binlog_cache_use | 0 | | Binlog_stmt_cache_disk_use | 0 | | Binlog_stmt_cache_use | 4 | | Bytes_received | 1343 | | Bytes_sent | 34853 | | Com_admin_commands | 0 | | Com_assign_to_keycache | 0 | | Com_alter_db | 0 | | Com_alter_db_upgrade | 0 | | Com_alter_event | 0 | | Com_alter_function | 0 | | Com_alter_procedure | 0 | | Com_alter_server | 0 | | Com_alter_table | 0 | | Com_alter_tablespace | 0 | | Com_alter_user | 0 | | Com_analyze | 0 | | Com_begin | 0 | | Com_binlog | 0 | | Com_call_procedure | 0 | | Com_change_db | 2 |
1.10 查看Mysql参数
mysql> show variablesG;
*************************** 1. row ***************************
Variable_name: auto_increment_increment
Value: 1
*************************** 2. row ***************************
Variable_name: auto_increment_offset
Value: 1
*************************** 3. row ***************************
Variable_name: autocommit
Value: ON
*************************** 4. row ***************************
Variable_name: automatic_sp_privileges
Value: ON
*************************** 5. row ***************************
Variable_name: avoid_temporal_upgrade
Value: OFF
1.11 修改Mysql的参数max_connect_errors
mysql> show variables like ‘max_connect%‘; +--------------------+-------+ | Variable_name | Value | +--------------------+-------+ | max_connect_errors | 100 | | max_connections | 151 | +--------------------+-------+ 2 rows in set (0.01 sec) mysql> set global max_connect_errors = 1000; Query OK, 0 rows affected (0.00 sec) mysql> show variables like ‘max_connect%‘;#类似shell命令行*通配符 +--------------------+-------+ | Variable_name | Value | +--------------------+-------+ | max_connect_errors | 1000 | | max_connections | 151 | +--------------------+-------+ 2 rows in set (0.00 sec) #set global临时更改参数，如果永久修改则需要在/etc/my.cnf配置文件中修改
1.12 查看当前Mysql服务器的队列
mysql> show processlist; +----+------+------------------+--------+-------------+------+-----------------------------------------------------------------------+------------------+ | Id | User | Host | db | Command | Time | State | Info | +----+------+------------------+--------+-------------+------+-----------------------------------------------------------------------+------------------+ | 2 | rep | 10.0.0.251:55984 | NULL | Binlog Dump | 3109 | Master has sent all binlog to slave; waiting for binlog to be updated | NULL | | 23 | root | localhost | zabbix | Query | 0 | init | show processlist | +----+------+------------------+--------+-------------+------+-----------------------------------------------------------------------+------------------+ 2 rows in set (0.00 sec) #查看当前Mysql在做什么操作，也可以是否有锁表
1.13 创建一个普通用户并授权
mysql> grant all on *.* to zabbix identified by ‘123456‘; Query OK, 0 rows affected (0.00 sec) #本地创建一个zabbix用户，授权所有权限 mysql> grant all on zabbix.* to ‘zabbix01‘@‘10.0.0.251‘ identified by ‘123456‘; Query OK, 0 rows affected (0.01 sec) #指定特定的网络机器登录mysql数据库并授权zabbix数据库下的所有表 mysql> grant all on zabbix.* to ‘zabbix02‘@‘%‘ identified by ‘123456‘; Query OK, 0 rows affected (0.00 sec) #指定所有主机登录mysql数据库并授权zabbix数据库下的所有表 mysql> select user,host from mysql.user where user like ‘zabbix%‘; +----------+------------+ | user | host | +----------+------------+ | zabbix | % | | zabbix02 | % | | zabbix01 | 10.0.0.251 | +----------+------------+ 3 rows in set (0.00 sec)
二、Mysql基本操作
2.1 查询语句
第一种查询方式： mysql> select count(*) from mysql.user; +----------+ | count(*) | +----------+ | 7 | +----------+ 1 row in set (0.00 sec) 第二种查询方式： mysql> select * from mysql.user; mysql> select user,host from mysql.user; +-----------+------------+ | user | host | +-----------+------------+ | zabbix | % | | zabbix02 | % | | rep | 10.0.0.% | | zabbix01 | 10.0.0.251 | | root | 127.0.0.1 | | root | localhost | | wordpress | localhost | +-----------+------------+ 7 rows in set (0.00 sec) mysql> select user,host from mysql.user where user like ‘zabbix%‘; +----------+------------+ | user | host | +----------+------------+ | zabbix | % | | zabbix02 | % | | zabbix01 | 10.0.0.251 | +----------+------------+ 3 rows in set (0.00 sec)
2.2 插入语句
mysql> insert into zabbix.user values(3,‘test‘,1111111111),(4,‘boy‘,222222222); Query OK, 2 rows affected (0.00 sec) Records: 2 Duplicates: 0 Warnings: 0 mysql> select * from zabbix.user where name=‘test‘ or name=‘boy‘; +------+------+------------+ | id | name | tel | +------+------+------------+ | 3 | test | 1111111111 | | 4 | boy | 222222222 | +------+------+------------+ 2 rows in set (0.00 sec)
2.3 更新表语句
mysql> update zabbix.user set name=‘girl‘ where id=3; Query OK, 1 row affected (1.69 sec) Rows matched: 1 Changed: 1 Warnings: 0 mysql> select * from zabbix.user where id=3; +------+------+------------+ | id | name | tel | +------+------+------------+ | 3 | girl | 1111111111 | +------+------+------------+ 1 row in set (0.00 sec)
2.4 清空表语句
mysql> truncate table zabbix.user; Query OK, 0 rows affected (0.09 sec) mysql> select * from zabbix.user; Empty set (0.00 sec)
2.5 删除表语句
mysql> drop table zabbix.user; Query OK, 0 rows affected (0.34 sec) mysql> show tables; Empty set (0.00 sec)
2.6 删除数据库
mysql> show databases like ‘zabbix%‘; +--------------------+ | Database (zabbix%) | +--------------------+ | zabbix | +--------------------+ 1 row in set (0.00 sec) mysql> drop database zabbix; Query OK, 0 rows affected (0.12 sec) mysql> show databases like ‘zabbix%‘; Empty set (0.00 sec)
三、Mysql数据备份与恢复
3.1 Mysql备份
[[email protected] ~]# mysqldump -u root -p123456 wordpress > /tmp/wordpress_ $(date +%F).sql Warning: Using a password on the command line interface can be insecure. [[email protected] ~]# ls -l /tmp/ total 784 -rw-r--r-- 1 root root 801875 Nov 11 17:33 wordpress_2018-11-11.sql
3.2 Mysql恢复
#删除原wordpress数据库 [[email protected] ~]# mysql -u root -p123456 -e ‘drop database wordpress;‘ Warning: Using a password on the command line interface can be insecure. #查看原wordpress数据库是否删除成功 [[email protected] ~]# mysql -u root -p123456 -e "show databases"; Warning: Using a password on the command line interface can be insecure. +--------------------+ | Database | +--------------------+ | information_schema | | dev | | guohua | | jumpserver | | mysql | | oldboy | | oldgirl | | performance_schema | | spdb | +--------------------+ #创建空的wordpress数据库 [[email protected] ~]# mysql -u root -p123456 -e "create database wordpress"; Warning: Using a password on the command line interface can be insecure. #查看新的wordpress数据是否新建完成 [[email protected] ~]# mysql -u root -p123456 -e "show databases like ‘wordpress%‘"; Warning: Using a password on the command line interface can be insecure. +-----------------------+ | Database (wordpress%) | +-----------------------+ | wordpress | +-----------------------+ #从以备份的wordpress恢复wordpres数据库 [[email protected] ~]# mysql -u root -p123456 wordpress < /tmp/wordpress_2018-11-11.sql Warning: Using a password on the command line interface can be insecure. #检查wordpress库是否恢复成功 [[email protected] ~]# mysql -u root -p123456 -e "use wordpress;show tables;" Warning: Using a password on the command line interface can be insecure. +-------------------------+ | Tables_in_wordpress | +-------------------------+ | wolf_commentmeta | | wolf_comments | | wolf_links | | wolf_options | | wolf_postmeta | | wolf_posts | | wolf_term_relationships | | wolf_term_taxonomy | | wolf_termmeta | | wolf_terms | | wolf_usermeta | | wolf_users | +-------------------------+
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