学习笔记0521----mysql管理
mysql管理
- 预习笔记
- 1. 设置更改root密码
- 1.1 设置MySQL的root密码
- 1.1.1 添加MySQL的bin目录到系统环境变量
- 1.1.2 检查MySQL是否启动
- 1.1.3 设置root密码
- 1.2 修改MySQL的root密码
- 1.2.1 知道root密码更改密码
- 1.2.1 忘记root密码更改密码
- 2. 连接MySQL方法
- 2.1 mysql -uroot -plinux002
- 2.2 mysql -uroot -plinux002 -h127.0.0.1 -P3306
- 2.3 mysql -uroot -plinux002 -S/tmp/mysql.sock
- 2.4 mysql -uroot -plinux002 -e "show databases"
- 3. MySQL常用命令
- 3.1 查询库 （show databases;）
- 3.2 切换库（use mysql;）
- 3.3 查看库里的表（show tables）
- 3.4 查看表里的字段（desc user;）
- 3.5 查看建表语句（show create table user\G;）
- 3.6 查看当前用户（select user();）
- 3.7 查看当前使用的数据库（select database();）
- 3.8 创建库（create database db1;）
- 3.9 创建表（create table t1(\`id\` int(4), \`name\` char(40)); ）
- 3.10 查看当前数据库版本（select version();）
- 3.11 查看数据库状态 （show status;）
- 3.11 查看表里的参数（show variables;）
- 3.12 修改参数（set global max_connect_errors=1000;）
- 3.13 查看队列（show processlist;）
- 4. MySQL用户管理
- 4.1 创建好用户提示无法登陆
- 4.2 创建的用户需要添加localhost的权限才可以登陆
- 5. 常用sql语句
- 5.1 统计一个表中有多少行
- 5.2 显示一个表中所有的内容
- 5.3 查询一个段或者多个段的数据
- 5.4 插入一行数据
- 5.5 更改表中数据
- 5.6 清空表中的数据，保留表结构
- 5.7 删除表
- 5.8 删除库
- 6. MySQL数据库备份恢复
- 6.1 备份库
- 6.2 恢复库
- 6.3 备份表
- 6.4 恢复表
- 6.5 备份所有库
- 6.6 只备份表结构
- 课后总结
预习笔记
13.1 设置更改root密码
13.2 连接mysql
13.3 mysql常用命令
13.4 mysql用户管理
13.5 常用sql语句
13.6 mysql数据库备份恢复
使用xtrabackup备份innodb引擎的数据库 innobackupex 备份 Xtrabackup 增量备份http://zhangguangzhi.top/2017/08/23/innobackex%E5%B7%A5%E5%85%B7%E5%A4%87%E4%BB%BDmysql%E6%95%B0%E6%8D%AE/#%E4%B8%89%E3%80%81%E5%BC%80%E5%A7%8B%E6%81%A2%E5%A4%8Dmysql
相关视频
链接：http://pan.baidu.com/s/1miFpS9M 密码：86dx
链接：http://pan.baidu.com/s/1o7GXBBW 密码：ue2f
扩展
mysql5.7 root密码更改 http://www.apelearn.com/bbs/thread-7289-1-1.html
myisam 和innodb引擎对比 http://www.pureweber.com/article/myisam-vs-innodb/
mysql 配置详解： http://blog.linuxeye.com/379.html
mysql调优： http://www.aminglinux.com/bbs/thread-5758-1-1.html
同学分享的亲身mysql调优经历： http://www.apelearn.com/bbs/thread-11281-1-1.html
SQL语句教程 http://www.runoob.com/sql/sql-tutorial.html
什么是事务？事务的特性有哪些？ http://blog.csdn.net/yenange/article/details/7556094
根据binlog恢复指定时间段的数据 https://blog.csdn.net/lilongsy/article/details/74726002
mysql字符集调整 http://xjsunjie.blog.51cto.com/999372/1355013
1. 设置更改root密码
1.1 设置MySQL的root密码
1.1.1 添加MySQL的bin目录到系统环境变量
MySQL的安装路径为：/usr/local/mysql/，可执行文件在bin目录下，此目录并未添加到系统的环境变量中，所以要使用mysql命令，需要把 /usr/local/mysql/bin/ 目录添加到系统的环境变量中。
## 临时添加到系统环境变量 ##
[root@linux-02 ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin
[root@linux-02 ~]# export PATH=$PATH:/usr/local/mysql/bin/
[root@linux-02 ~]# !echo
echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin:/usr/local/mysql/bin/:/usr/local/mysql/bin/
## 永久添加到系统环境变量 ##
[root@linux-02 ~]# vim /etc/profile
## 添加以下内容 ##
export PATH=$PATH:/usr/local/mysql/bin/
[root@linux-02 ~]# source /etc/profile
1.1.2 检查MySQL是否启动
在使用mysql命令的时候需要先启动mysql，检查下系统是否有启动MySQL，如果没有启动，使用 /etc/init.d/mysqld start 启动MySQL。
[root@linux-02 ~]# ps aux | grep mysql
root 7050 0.0 0.0 115644 1816 ? S 5月20 0:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --datadir=/data/mysql --pid-file=/data/mysql/linux-02.pid
mysql 7255 0.0 24.4 1303012 455456 ? Sl 5月20 0:11 /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/data/mysql --plugin-dir=/usr/local/mysql/lib/plugin --user=mysql --log-error=linux-02.err --pid-file=/data/mysql/linux-02.pid --socket=/tmp/mysql.sock
root 7949 0.0 0.0 112728 988 pts/0 S+ 00:20 0:00 grep --color=auto mysql
[root@linux-02 ~]#
1.1.3 设置root密码
mysql启动，第一次进MySQL数据库root是没有密码，为了安全起见，还是需要给root设置一个密码。使用 mysqladmin -uroot password ‘mysql’ 给root用户添加密码。
[root@linux-02 ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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
## 给MySQL中的root用户添加密码 ##
[root@linux-02 ~]# mysqladmin -uroot password 'mysql'
Warning: Using a password on the command line interface can be insecure.
[root@linux-02 ~]# mysql -uroot -pmysql
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 4
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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>
mysql> quit
Bye
1.2 修改MySQL的root密码
1.2.1 知道root密码更改密码
在使用MySQL的时候，我们知道root的密码的时候，如果要更改密码可以使用mysqladmin，具体操作如下。
[root@linux-02 ~]# mysqladmin -uroot -p'mysql' password '123456'
Warning: Using a password on the command line interface can be insecure.
[root@linux-02 ~]# mysql -uroot -p123456
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 6
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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
[root@linux-02 ~]#
1.2.1 忘记root密码更改密码
- 如果忘记MySQL的root密码，更改mysql密码需要进行以下几步操作：
- 修改/etc/my.cnf ,在mysqld模块添加：skip-grant
- 重启MySQL服务：/etc/init.d/mysqld restart
- 使用 mysql -uroot -p 无密码进入MySQL
- 切换到mysql的数据库：use mysql ；
- 执行命令：update user set password=password(‘linux002’) where user=‘root’;
- 退出mysql：quit
- 修改/etc/my.cnf ，删除刚才添加的skip-grant
- 重启MySQL服务
[root@linux-02 ~]# vim /etc/my.cnf
## 添加如下内容 ##
skip-grant
[root@linux-02 ~]# service mysqld restart
Shutting down MySQL.. SUCCESS!
Starting MySQL. SUCCESS!
[root@linux-02 ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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;
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> update user set password=password('linux002') where user='root';
Query OK, 0 rows affected (0.00 sec)
Rows matched: 4 Changed: 0 Warnings: 0
mysql> quit
Bye
[root@linux-02 ~]# vim /etc/my.cnf
## 删除添加的内容，可以加#号注释 ##
# skip-grant
[root@linux-02 ~]# !servi
service mysqld restart
Shutting down MySQL.. SUCCESS!
Starting MySQL. SUCCESS!
[root@linux-02 ~]# mysql -uroot -plinux002
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 1
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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
[root@linux-02 ~]#
2. 连接MySQL方法
2.1 mysql -uroot -plinux002
默认连接本机的mysql，端口3306。
[root@linux-02 ~]# mysql -uroot -plinux002
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 2
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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
2.2 mysql -uroot -plinux002 -h127.0.0.1 -P3306
使用此方式常用于远程连接MySQL。
[root@linux-02 ~]# mysql -uroot -plinux002 -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.
Your MySQL connection id is 3
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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
[root@linux-02 ~]#
2.3 mysql -uroot -plinux002 -S/tmp/mysql.sock
指定sock文件连接MySQL，仅用于本机。
[root@linux-02 ~]# mysql -uroot -plinux002 -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.
Your MySQL connection id is 4
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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
[root@linux-02 ~]#
2.4 mysql -uroot -plinux002 -e “show databases”
常用于脚本中。
[root@linux-02 ~]# mysql -uroot -plinux002 -e "show databases"
Warning: Using a password on the command line interface can be insecure.
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
+--------------------+
[root@linux-02 ~]#
3. MySQL常用命令
3.1 查询库 （show databases;）
[root@linux-02 ~]# mysql -uroot -plinux002 -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.
Your MySQL connection id is 6
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
+--------------------+
4 rows in set (0.00 sec)
mysql>
3.2 切换库（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
mysql>
3.3 查看库里的表（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)
mysql>
3.4 查看表里的字段（desc user;）
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 (0.00 sec)
mysql> desc user;
3.5 查看建表语句（show create table user\G;）
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 (0.00 sec)
ERROR:
No query specified
mysql>
3.6 查看当前用户（select user();）
mysql> select user();
+----------------+
| user() |
+----------------+
| root@localhost |
+----------------+
1 row in set (0.00 sec)
mysql>
3.7 查看当前使用的数据库（select database();）
mysql> select database();
+------------+
| database() |
+------------+
| mysql |
+------------+
1 row in set (0.00 sec)
mysql>
3.8 创建库（create database db1;）
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>
3.9 创建表（create table t1(`id` int(4), `name` char(40)); ）
create table t1(`id` int(4), `name` char(40)); --t1为名字 id、name为字段 int为格式 char字符串最长40。
mysql> use db1;
Database changed
mysql> create table t1(`id` int(4), `name` char(40));
Query OK, 0 rows affected (0.01 sec)
mysql> show create table t1\G;
*************************** 1. row ***************************
Table: t1
Create Table: CREATE TABLE `t1` (
`id` int(4) DEFAULT NULL,
`name` char(40) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1
1 row in set (0.00 sec)
ERROR:
No query specified
mysql>
3.10 查看当前数据库版本（select version();）
mysql> select version();
+-----------+
| version() |
+-----------+
| 5.6.43 |
+-----------+
1 row in set (0.00 sec)
mysql>
3.11 查看数据库状态 （show status;）
mysql> show status;
+-----------------------------------------------+-------------+
| Variable_name | Value |
+-----------------------------------------------+-------------+
| Aborted_clients | 0 |
| Aborted_connects | 0 |
| Binlog_cache_disk_use | 0 |
| Binlog_cache_use | 0 |
| Binlog_stmt_cache_disk_use | 0 |
| Binlog_stmt_cache_use | 0 |
| Bytes_received | 1170 |
| Bytes_sent | 31193 |
| 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 |
| Com_change_master | 0 |
| Com_check | 0 |
| Com_checksum | 0 |
| Com_commit | 0 |
| Com_create_db | 1 |
| Com_create_event | 0 |
| Com_create_function | 0 |
| Com_create_index | 0 |
| Com_create_procedure | 0 |
| Com_create_server | 0 |
| Com_create_table | 1 |
| Com_create_trigger | 0 |
| Com_create_udf | 0 |
| Com_create_user | 0 |
| Com_create_view | 0 |
| Com_dealloc_sql | 0 |
| Com_delete | 0 |
| Com_delete_multi | 0 |
| Com_do | 0 |
| Com_drop_db | 0 |
| Com_drop_event | 0 |
| Com_drop_function | 0 |
| Com_drop_index | 0 |
| Com_drop_procedure | 0 |
| Com_drop_server | 0 |
| Com_drop_table | 0 |
| Com_drop_trigger | 0 |
| Com_drop_user | 0 |
| Com_drop_view | 0 |
| Com_empty_query | 0 |
| Com_execute_sql | 0 |
| Com_flush | 0 |
| Com_get_diagnostics | 0 |
| Com_grant | 0 |
| Com_ha_close | 0 |
| Com_ha_open | 0 |
| Com_ha_read | 0 |
| Com_help | 0 |
| Com_insert | 0 |
| Com_insert_select | 0 |
| Com_install_plugin | 0 |
| Com_kill | 0 |
| Com_load | 0 |
| Com_lock_tables | 0 |
| Com_optimize | 0 |
| Com_preload_keys | 0 |
| Com_prepare_sql | 0 |
| Com_purge | 0 |
| Com_purge_before_date | 0 |
| Com_release_savepoint | 0 |
| Com_rename_table | 0 |
| Com_rename_user | 0 |
| Com_repair | 0 |
| Com_replace | 0 |
| Com_replace_select | 0 |
| Com_reset | 0 |
| Com_resignal | 0 |
| Com_revoke | 0 |
| Com_revoke_all | 0 |
| Com_rollback | 0 |
| Com_rollback_to_savepoint | 0 |
| Com_savepoint | 0 |
| Com_select | 6 |
| Com_set_option | 0 |
| Com_signal | 0 |
| Com_show_binlog_events | 0 |
| Com_show_binlogs | 0 |
| Com_show_charsets | 0 |
| Com_show_collations | 0 |
| Com_show_create_db | 0 |
| Com_show_create_event | 0 |
| Com_show_create_func | 0 |
| Com_show_create_proc | 0 |
| Com_show_create_table | 3 |
| Com_show_create_trigger | 0 |
| Com_show_databases | 4 |
| Com_show_engine_logs | 0 |
| Com_show_engine_mutex | 0 |
| Com_show_engine_status | 0 |
| Com_show_events | 0 |
| Com_show_errors | 0 |
| Com_show_fields | 29 |
| Com_show_function_code | 0 |
| Com_show_function_status | 0 |
| Com_show_grants | 0 |
| Com_show_keys | 0 |
| Com_show_master_status | 0 |
| Com_show_open_tables | 0 |
| Com_show_plugins | 0 |
| Com_show_privileges | 0 |
| Com_show_procedure_code | 0 |
| Com_show_procedure_status | 0 |
| Com_show_processlist | 0 |
| Com_show_profile | 0 |
| Com_show_profiles | 0 |
| Com_show_relaylog_events | 0 |
| Com_show_slave_hosts | 0 |
| Com_show_slave_status | 0 |
| Com_show_status | 1 |
| Com_show_storage_engines | 0 |
| Com_show_table_status | 0 |
| Com_show_tables | 3 |
| Com_show_triggers | 0 |
| Com_show_variables | 0 |
| Com_show_warnings | 0 |
| Com_slave_start | 0 |
| Com_slave_stop | 0 |
| Com_stmt_close | 0 |
| Com_stmt_execute | 0 |
| Com_stmt_fetch | 0 |
| Com_stmt_prepare | 0 |
| Com_stmt_reprepare | 0 |
| Com_stmt_reset | 0 |
| Com_stmt_send_long_data | 0 |
| Com_truncate | 0 |
| Com_uninstall_plugin | 0 |
| Com_unlock_tables | 0 |
| Com_update | 0 |
| Com_update_multi | 0 |
| Com_xa_commit | 0 |
| Com_xa_end | 0 |
| Com_xa_prepare | 0 |
| Com_xa_recover | 0 |
| Com_xa_rollback | 0 |
| Com_xa_start | 0 |
| Compression | OFF |
| Connection_errors_accept | 0 |
| Connection_errors_internal | 0 |
| Connection_errors_max_connections | 0 |
| Connection_errors_peer_address | 0 |
| Connection_errors_select | 0 |
| Connection_errors_tcpwrap | 0 |
| Connections | 7 |
| Created_tmp_disk_tables | 1 |
| Created_tmp_files | 6 |
| Created_tmp_tables | 8 |
| Delayed_errors | 0 |
| Delayed_insert_threads | 0 |
| Delayed_writes | 0 |
| Flush_commands | 1 |
| Handler_commit | 0 |
| Handler_delete | 0 |
| Handler_discover | 0 |
| Handler_external_lock | 0 |
| Handler_mrr_init | 0 |
| Handler_prepare | 0 |
| Handler_read_first | 0 |
| Handler_read_key | 0 |
| Handler_read_last | 0 |
| Handler_read_next | 0 |
| Handler_read_prev | 0 |
| Handler_read_rnd | 0 |
| Handler_read_rnd_next | 125 |
| Handler_rollback | 0 |
| Handler_savepoint | 0 |
| Handler_savepoint_rollback | 0 |
| Handler_update | 0 |
| Handler_write | 117 |
| Innodb_buffer_pool_dump_status | not started |
| Innodb_buffer_pool_load_status | not started |
| Innodb_buffer_pool_pages_data | 170 |
| Innodb_buffer_pool_bytes_data | 2785280 |
| Innodb_buffer_pool_pages_dirty | 0 |
| Innodb_buffer_pool_bytes_dirty | 0 |
| Innodb_buffer_pool_pages_flushed | 17 |
| Innodb_buffer_pool_pages_free | 8021 |
| Innodb_buffer_pool_pages_misc | 0 |
| Innodb_buffer_pool_pages_total | 8191 |
| Innodb_buffer_pool_read_ahead_rnd | 0 |
| Innodb_buffer_pool_read_ahead | 0 |
| Innodb_buffer_pool_read_ahead_evicted | 0 |
| Innodb_buffer_pool_read_requests | 696 |
| Innodb_buffer_pool_reads | 167 |
| Innodb_buffer_pool_wait_free | 0 |
| Innodb_buffer_pool_write_requests | 47 |
| Innodb_data_fsyncs | 17 |
| Innodb_data_pending_fsyncs | 0 |
| Innodb_data_pending_reads | 0 |
| Innodb_data_pending_writes | 0 |
| Innodb_data_read | 2805760 |
| Innodb_data_reads | 182 |
| Innodb_data_writes | 29 |
| Innodb_data_written | 564736 |
| Innodb_dblwr_pages_written | 17 |
| Innodb_dblwr_writes | 2 |
| Innodb_have_atomic_builtins | ON |
| Innodb_log_waits | 0 |
| Innodb_log_write_requests | 9 |
| Innodb_log_writes | 4 |
| Innodb_os_log_fsyncs | 7 |
| Innodb_os_log_pending_fsyncs | 0 |
| Innodb_os_log_pending_writes | 0 |
| Innodb_os_log_written | 6144 |
| Innodb_page_size | 16384 |
| Innodb_pages_created | 4 |
| Innodb_pages_read | 166 |
| Innodb_pages_written | 17 |
| Innodb_row_lock_current_waits | 0 |
| Innodb_row_lock_time | 0 |
| Innodb_row_lock_time_avg | 0 |
| Innodb_row_lock_time_max | 0 |
| Innodb_row_lock_waits | 0 |
| Innodb_rows_deleted | 0 |
| Innodb_rows_inserted | 0 |
| Innodb_rows_read | 0 |
| Innodb_rows_updated | 0 |
| Innodb_num_open_files | 9 |
| Innodb_truncated_status_writes | 0 |
| Innodb_available_undo_logs | 128 |
| Key_blocks_not_flushed | 0 |
| Key_blocks_unused | 6698 |
| Key_blocks_used | 0 |
| Key_read_requests | 0 |
| Key_reads | 0 |
| Key_write_requests | 0 |
| Key_writes | 0 |
| Last_query_cost | 0.000000 |
| Last_query_partial_plans | 0 |
| Max_used_connections | 1 |
| Not_flushed_delayed_rows | 0 |
| Open_files | 46 |
| Open_streams | 0 |
| Open_table_definitions | 81 |
| Open_tables | 81 |
| Opened_files | 163 |
| Opened_table_definitions | 15 |
| Opened_tables | 21 |
| Performance_schema_accounts_lost | 0 |
| Performance_schema_cond_classes_lost | 0 |
| Performance_schema_cond_instances_lost | 0 |
| Performance_schema_digest_lost | 0 |
| Performance_schema_file_classes_lost | 0 |
| Performance_schema_file_handles_lost | 0 |
| Performance_schema_file_instances_lost | 0 |
| Performance_schema_hosts_lost | 0 |
| Performance_schema_locker_lost | 0 |
| Performance_schema_mutex_classes_lost | 0 |
| Performance_schema_mutex_instances_lost | 0 |
| Performance_schema_rwlock_classes_lost | 0 |
| Performance_schema_rwlock_instances_lost | 0 |
| Performance_schema_session_connect_attrs_lost | 0 |
| Performance_schema_socket_classes_lost | 0 |
| Performance_schema_socket_instances_lost | 0 |
| Performance_schema_stage_classes_lost | 0 |
| Performance_schema_statement_classes_lost | 0 |
| Performance_schema_table_handles_lost | 0 |
| Performance_schema_table_instances_lost | 0 |
| Performance_schema_thread_classes_lost | 0 |
| Performance_schema_thread_instances_lost | 0 |
| Performance_schema_users_lost | 0 |
| Prepared_stmt_count | 0 |
| Qcache_free_blocks | 1 |
| Qcache_free_memory | 1031352 |
| Qcache_hits | 0 |
| Qcache_inserts | 0 |
| Qcache_lowmem_prunes | 0 |
| Qcache_not_cached | 11 |
| Qcache_queries_in_cache | 0 |
| Qcache_total_blocks | 1 |
| Queries | 62 |
| Questions | 50 |
| Select_full_join | 0 |
| Select_full_range_join | 0 |
| Select_range | 0 |
| Select_range_check | 0 |
| Select_scan | 8 |
| Slave_heartbeat_period | |
| Slave_last_heartbeat | |
| Slave_open_temp_tables | 0 |
| Slave_received_heartbeats | |
| Slave_retried_transactions | |
| Slave_running | OFF |
| Slow_launch_threads | 0 |
| Slow_queries | 0 |
| Sort_merge_passes | 0 |
| Sort_range | 0 |
| Sort_rows | 0 |
| Sort_scan | 0 |
| Ssl_accept_renegotiates | 0 |
| Ssl_accepts | 0 |
| Ssl_callback_cache_hits | 0 |
| Ssl_cipher | |
| Ssl_cipher_list | |
| Ssl_client_connects | 0 |
| Ssl_connect_renegotiates | 0 |
| Ssl_ctx_verify_depth | 0 |
| Ssl_ctx_verify_mode | 0 |
| Ssl_default_timeout | 0 |
| Ssl_finished_accepts | 0 |
| Ssl_finished_connects | 0 |
| Ssl_server_not_after | |
| Ssl_server_not_before | |
| Ssl_session_cache_hits | 0 |
| Ssl_session_cache_misses | 0 |
| Ssl_session_cache_mode | NONE |
| Ssl_session_cache_overflows | 0 |
| Ssl_session_cache_size | 0 |
| Ssl_session_cache_timeouts | 0 |
| Ssl_sessions_reused | 0 |
| Ssl_used_session_cache_entries | 0 |
| Ssl_verify_depth | 0 |
| Ssl_verify_mode | 0 |
| Ssl_version | |
| Table_locks_immediate | 70 |
| Table_locks_waited | 0 |
| Table_open_cache_hits | 11 |
| Table_open_cache_misses | 21 |
| Table_open_cache_overflows | 0 |
| Tc_log_max_pages_used | 0 |
| Tc_log_page_size | 0 |
| Tc_log_page_waits | 0 |
| Threads_cached | 0 |
| Threads_connected | 1 |
| Threads_created | 1 |
| Threads_running | 1 |
| Uptime | 10901 |
| Uptime_since_flush_status | 10901 |
+-----------------------------------------------+-------------+
341 rows in set (0.01 sec)
mysql>
3.11 查看表里的参数（show variables;）
mysql> show variables like "version";
+---------------+--------+
| Variable_name | Value |
+---------------+--------+
| version | 5.6.43 |
+---------------+--------+
1 row in set (0.00 sec)
mysql> show variables like "version%";
+-------------------------+------------------------------+
| Variable_name | Value |
+-------------------------+------------------------------+
| version | 5.6.43 |
| version_comment | MySQL Community Server (GPL) |
| version_compile_machine | x86_64 |
| version_compile_os | linux-glibc2.12 |
+-------------------------+------------------------------+
4 rows in set (0.00 sec)
mysql>
3.12 修改参数（set global max_connect_errors=1000;）
global只是临时修改，要永久生效需要去配置文件添加。
mysql> show variables like "max_con%";
+--------------------+-------+
| Variable_name | Value |
+--------------------+-------+
| max_connect_errors | 100 |
| max_connections | 151 |
+--------------------+-------+
2 rows in set (0.00 sec)
mysql> set global max_connect_errors=1000 ;
Query OK, 0 rows affected (0.00 sec)
mysql> show variables like "max_con%";
+--------------------+-------+
| Variable_name | Value |
+--------------------+-------+
| max_connect_errors | 1000 |
| max_connections | 151 |
+--------------------+-------+
2 rows in set (0.00 sec)
mysql>
3.13 查看队列（show processlist;）
查看当前mysql服务器的队列：
查看服务器队列可以查看当前mysql在干什么，也可以发行是否有锁表！
show processlist;
show full processlist; 完整查看（可以看到info这里显示比较完整）
mysql> show processlist;
+----+------+-----------+------+---------+------+-------+------------------+
| Id | User | Host | db | Command | Time | State | Info |
+----+------+-----------+------+---------+------+-------+------------------+
| 6 | root | localhost | db1 | Query | 0 | init | show processlist |
+----+------+-----------+------+---------+------+-------+------------------+
1 row in set (0.00 sec)
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)
mysql>
4. MySQL用户管理
- mysql> grant all privileges on . to jack@‘localhost’ identified by “jack” with grant option;
Query OK, 0 rows affected (0.01 sec) - GRANT命令说明：
- ALL PRIVILEGES 是表示所有权限，你也可以使用select、update等权限。
- ON 用来指定权限针对哪些库和表。
- . 中前面的号用来指定数据库名，后面的号用来指定表名。
- TO 表示将权限赋予某个用户。
- jack@‘localhost’ 表示jack用户，@后面接限制的主机，可以是IP、IP段、域名以及%，%表示任何地方。注意：这里%有的版本不包括本地，以前碰到过给某个用户设置了%允许任何地方登录，但是在本地登录不了，这个和版本有关系，遇到这个问题再加一个localhost的用户就可以了。
- IDENTIFIED BY 指定用户的登录密码。
- WITH GRANT OPTION 这个选项表示该用户可以将自己拥有的权限授权给别人。注意：经常有人在创建操作用户的时候不指定WITH GRANT OPTION选项导致后来该用户不能使用GRANT命令创建用户或者给其它用户授权。
备注：可以使用GRANT重复给用户添加权限，权限叠加，比如你先给用户添加一个select权限，然后又给用户添加一个insert权限，那么该用户就同时拥有了select和insert权限。
4.1 创建好用户提示无法登陆
[root@linux-02 ~]# mysql -uroot -plinux002
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 12
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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> grant all on *.* to user1@'%' identified by ’123456‘ ；
Query OK, 0 rows affected (0.00 sec)
mysql> show grants for user1;
+---------------------------------------------------------------------------------------------------------------+
| Grants for user1@% |
+---------------------------------------------------------------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'user1'@'%' IDENTIFIED BY PASSWORD '*6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9' |
+---------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
mysql> exit
Bye
[root@linux-02 ~]# mysql -uuser1 -p123456
Warning: Using a password on the command line interface can be insecure.
ERROR 1045 (28000): Access denied for user 'user1'@'localhost' (using password: YES)
4.2 创建的用户需要添加localhost的权限才可以登陆
- 无法登录原因：
- 其中两个账户有相同的用户名monty和密码some_pass。两个账户均为超级用户账户，具有完全的权限可以做任何事情。一个账户 (‘monty’@‘localhost’)只用于从本机连接时。另一个账户(‘monty’@’%’)可用于从其它主机连接。请注意monty的两个账户必须能从任何主机以monty连接。没有localhost账户，当monty从本机连接时，mysql_install_db创建的localhost的匿名用户账户将占先。结果是，monty将被视为匿名用户。原因是匿名用户账户的Host列值比’monty’@’%'账户更具体，这样在user表排序顺序中排在前面。
[root@linux-02 ~]# mysql -uroot -plinux002
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 15
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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> grant all on *.* to user1@'localhost' identified by '123456';
Query OK, 0 rows affected (0.00 sec)
mysql> exit
Bye
[root@linux-02 ~]# mysql -uuser1 -p123456
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 16
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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> show grants for user1 ;
+---------------------------------------------------------------------------------------------------------------+
| Grants for user1@% |
+---------------------------------------------------------------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'user1'@'%' IDENTIFIED BY PASSWORD '*6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9' |
+---------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
mysql> show grants;
+-----------------------------------------------------------------------------------------------------------------------+
| Grants for user1@localhost |
+-----------------------------------------------------------------------------------------------------------------------+
| GRANT ALL PRIVILEGES ON *.* TO 'user1'@'localhost' IDENTIFIED BY PASSWORD '*6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9' |
+-----------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
mysql> exit
Bye
5. 常用sql语句
5.1 统计一个表中有多少行
- select count(*) from db1.t1;
- 其中 db1表示库名，t1表示表名，中间用点隔开。此命令尽量少用，如果数据有几百万条，很容易浪费mysql的资源。
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| db1 |
| mysql |
| performance_schema |
| test |
+--------------------+
5 rows in set (0.00 sec)
mysql> use db1;
Database changed
mysql> show tables ;
+---------------+
| Tables_in_db1 |
+---------------+
| t1 |
+---------------+
1 row in set (0.00 sec)
mysql> select count(*) from db1.t1;
+----------+
| count(*) |
+----------+
| 0 |
+----------+
1 row in set (0.00 sec)
mysql> select * from db1.t1;
Empty set (0.00 sec)
mysql>
5.2 显示一个表中所有的内容
- select * from mysql.db;
- 此命令也要少用，在数据量很大的时候，使用此命令占用mysql很大的资源。
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)
mysql> select * from mysql.db;
+------+---------+------+-------------+-------------+-------------+-------------+-------------+-----------+------------+-----------------+------------+------------+-----------------------+------------------+------------------+----------------+---------------------+--------------------+--------------+------------+--------------+
| Host | Db | User | Select_priv | Insert_priv | Update_priv | Delete_priv | Create_priv | Drop_priv | Grant_priv | References_priv | Index_priv | Alter_priv | Create_tmp_table_priv | Lock_tables_priv | Create_view_priv | Show_view_priv | Create_routine_priv | Alter_routine_priv | Execute_priv | Event_priv | Trigger_priv |
+------+---------+------+-------------+-------------+-------------+-------------+-------------+-----------+------------+-----------------+------------+------------+-----------------------+------------------+------------------+----------------+---------------------+--------------------+--------------+------------+--------------+
| % | test | | Y | Y | Y | Y | Y | Y | N | Y | Y | Y | Y | Y | Y | Y | Y | N | N | Y | Y |
| % | test\_% | | Y | Y | Y | Y | Y | Y | N | Y | Y | Y | Y | Y | Y | Y | Y | N | N | Y | Y |
+------+---------+------+-------------+-------------+-------------+-------------+-------------+-----------+------------+-----------------+------------+------------+-----------------------+------------------+------------------+----------------+---------------------+--------------------+--------------+------------+--------------+
2 rows in set (0.00 sec)
mysql> select * from mysql.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
*************************** 2. 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
2 rows in set (0.00 sec)
ERROR:
No query specified
mysql>
5.3 查询一个段或者多个段的数据
- select db,host from mysql.db;
- 其中db段和host段之间需要使用逗号隔开。
mysql> select db from mysql.db;
+---------+
| db |
+---------+
| test |
| test\_% |
+---------+
2 rows in set (0.00 sec)
mysql> select db,host from mysql.db;
+---------+------+
| db | host |
+---------+------+
| test | % |
| test\_% | % |
+---------+------+
2 rows in set (0.00 sec)
mysql>
5.4 插入一行数据
- insert into db1.t1 values (234,‘qwe’);
- 插入数据的时候，是字符串的值，建议加上单引号。
mysql> use db1
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_db1 |
+---------------+
| t1 |
+---------------+
1 row in set (0.01 sec)
mysql> select * from db1.t1;
Empty set (0.00 sec)
mysql> insert into db1.t1 values (234,'qwe');
Query OK, 1 row affected (0.05 sec)
mysql> select * from db1.t1;
+------+------+
| id | name |
+------+------+
| 234 | qwe |
+------+------+
1 row in set (0.00 sec)
mysql>
5.5 更改表中数据
- update db1.t1 set name=‘linux’ where id=234;
mysql> select * from db1.t1;
+------+------+
| id | name |
+------+------+
| 234 | qwe |
+------+------+
1 row in set (0.00 sec)
mysql> update db1.t1 set name='linux' where id=234;
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> select * from db1.t1;
+------+-------+
| id | name |
+------+-------+
| 234 | linux |
+------+-------+
1 row in set (0.00 sec)
mysql>
5.6 清空表中的数据，保留表结构
- truncate table db1.t1;
- 此命令和drop不同的是，操作紧紧是把表中的数据给删除，表结构保留。
mysql> select * from db1.t1;
+------+-------+
| id | name |
+------+-------+
| 234 | linux |
+------+-------+
1 row in set (0.00 sec)
mysql>
mysql> truncate table db1.t1;
Query OK, 0 rows affected (0.01 sec)
mysql> select * from db1.t1;
Empty set (0.00 sec)
mysql> desc db1.t1;
+-------+----------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| id | int(4) | YES | | NULL | |
| name | char(40) | YES | | NULL | |
+-------+----------+------+-----+---------+-------+
2 rows in set (0.00 sec)
mysql>
5.7 删除表
mysql> show tables;
+---------------+
| Tables_in_db1 |
+---------------+
| t1 |
+---------------+
1 row in set (0.00 sec)
mysql> drop table db1.t1;
Query OK, 0 rows affected (0.00 sec)
mysql> show tables;
Empty set (0.00 sec)
mysql>
5.8 删除库
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| db1 |
| mysql |
| performance_schema |
| test |
+--------------------+
5 rows in set (0.00 sec)
mysql> drop database db1;
Query OK, 0 rows affected (0.04 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
+--------------------+
4 rows in set (0.00 sec)
mysql>
6. MySQL数据库备份恢复
6.1 备份库
- mysqldump -uroot -plinux002 mysql > /data/mysql.bak/mysql.sql
[root@linux-02 ~]# mysqldump -uroot -plinux002 mysql > /data/mysql.bak/mysql.sql
Warning: Using a password on the command line interface can be insecure.
[root@linux-02 ~]# du -sh /data/mysql.bak/mysql.sql
632K /data/mysql.bak/mysql.sql
[root@linux-02 ~]#
6.2 恢复库
- mysql -uroot -plinux002 mysql < /data/mysql.bak/mysql.sql
- 先把需要恢复的库创建好。
[root@linux-02 ~]# mysql -uroot -plinux002
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 7
Server version: 5.6.43 MySQL Community Server (GPL)
Copyright (c) 2000, 2019, 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> create database mysql ;
Query OK, 1 row affected (0.00 sec)
mysql> exit
Bye
[root@linux-02 ~]# mysql -uroot -plinux002 mysql < /data/mysql.bak/mysql.sql
Warning: Using a password on the command line interface can be insecure.
[root@linux-02 ~]#
6.3 备份表
- mysqldump -uroot -plinux002 mysql user > /data/mysql.bak/mysql_user.sql
- mysql 是库名，user 是表名，中间使用空格隔开
[root@linux-02 ~]# mysqldump -uroot -plinux002 mysql user > /data/mysql.bak/mysql_user.sql
Warning: Using a password on the command line interface can be insecure.
[root@linux-02 ~]# du -sh /data/mysql.bak/mysql_user.sql
8.0K /data/mysql.bak/mysql_user.sql
[root@linux-02 ~]#
6.4 恢复表
- mysql -uroot -plinux002 mysql < /data/mysql.bak/mysql_user.sql
- 恢复表时不需要指定表名，只需要指定库名即可
[root@linux-02 ~]# mysql -uroot -plinux002 mysql < /data/mysql.bak/mysql_user.sql
Warning: Using a password on the command line interface can be insecure.
6.5 备份所有库
- mysqldump -uroot -plinux002 -A >/data/mysql.bak/all_data.sql
- -A 指定备份所有库
- 在恢复库的时候同样需要先创建好库名称才可以恢复。
[root@linux-02 ~]# mysqldump -uroot -plinux002 -A > /data/mysql.bak/all_data.sql
Warning: Using a password on the command line interface can be insecure.
[root@linux-02 ~]# du -sh /data/mysql.bak/all_data.sql
632K /data/mysql.bak/all_data.sql
[root@linux-02 ~]#
6.6 只备份表结构
- mysqldump -uroot -plinux002 -d > /data/mysql.bak/all_data_list.sql
- -d 指定备份表结构
[root@linux-02 ~]# mysqldump -uroot -plinux002 -d > /data/mysql.bak/all_data_list.sql
Warning: Using a password on the command line interface can be insecure.
[root@linux-02 ~]# du -sh !$
du -sh /data/mysql.bak/all_data_list.sql
4.0K /data/mysql.bak/all_data_list.sql
[root@linux-02 ~]#
课后总结
mysql版本变化
https://www.cnblogs.com/ivictor/p/9807284.html
mariadb的版本变化
https://downloads.mariadb.org/
主从：
https://blog.csdn.net/xiaoyi23000/article/details/80521423
https://blog.csdn.net/u013399093/article/details/70568837
https://www.cnblogs.com/abobo/p/4242417.html
mysql参数调整
http://isky000.com/database/mysql-perfornamce-tuning-cache-parameter