Part1:写在最前
MySQL安装的方式有三种：
①rpm包安装
②二进制包安装
③源码安装
这里我们推荐二进制包安装，无论从安装速度还是用于生产库安装环境来说，都是没问题的。现在生产库一般采用MySQL5.6，测试库采用MySQL5.7。
MySQL5.6安装看这里
http://suifu.blog.51cto.com/9167728/1846671
MySQL5.7安装看这里
http://suifu.blog.51cto.com/9167728/1855415
8分钟数据库操作
Part1:登录
MySQL的登录方式为：
-u为用户名，-p为密码，如果您用了上述本文的安装脚本，默认密码为MANAGER
[root@HE3 ~]# mysql -uroot -pMANAGER
mysql: [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 11
Server version: 5.7.16-log MySQL Community Server (GPL)
Copyright (c) 2000, 2016, 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>
Part2:表基础操作
①查看数据库中有哪些库
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| he1 |
| he3 |
| maxscale |
| mysql |
| performance_schema |
| sys |
+--------------------+
7 rows in set (0.00 sec)
②增删改查
同Excel一样，数据库中也是要增删改查的主要涉及的语法如下：
查：
首先选择相应的库
mysql> use maxscale
Database changed
select * from 表名;是查询这张表所有内容的意思；
select 列名,列名 from 表名;是查询这张表想看的列内容；
mysql> select a,b from helei;
+--------+------+
| a | b |
+--------+------+
| HE3 | a |
| 写入 | b |
| 测试 | c |
| 于浩 | d |
| 贺磊 | e |
+--------+------+
6 rows in set (0.00 sec)
增：
insert into 表名 values('想插入的内容'); 往表中插入一条记录的意思；
mysql> insert into helei values('插入','f');
Query OK, 1 row affected (0.01 sec)
mysql> select a,b from helei;
+--------+------+
| a | b |
+--------+------+
| HE3 | a |
| 写入 | b |
| 测试 | c |
| 于浩 | d |
| 贺磊 | e |
| 插入 | f |
+--------+------+
6 rows in set (0.00 sec)
我这里表名叫helei;
删：
delete from helei where b='f';删除helei表中b列是f的所有记录；
mysql> delete from helei where b='f';
Query OK, 1 row affected (0.01 sec)
mysql> select * from helei;
+--------+------+
| a | b |
+--------+------+
| HE3 | a |
| 写入 | b |
| 测试 | c |
| 于浩 | d |
| 贺磊 | e |
+--------+------+
5 rows in set (0.00 sec)
可以看到这里b列为f的整个一行就被删除掉了。
改：
update 表名 set 列名='改成所需内容' where 限定条件。
mysql> update helei set b='改' where a='贺磊';
Query OK, 1 row affected (0.01 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> select * from helei;
+--------+------+
| a | b |
+--------+------+
| HE3 | a |
| 写入 | b |
| 测试 | c |
| 于浩 | d |
| 贺磊 | 改 |
+--------+------+
5 rows in set (0.00 sec)
③表级操作
创建表
创建表t,这里用生产库的来做例子，id列自增主键，log为varchar类型，可以存30个字符；
mysql> CREATE TABLE `t` (
-> `id` int UNSIGNED NOT NULL AUTO_INCREMENT ,
-> `log` varchar(30) NOT NULL DEFAULT '' ,
-> PRIMARY KEY (`id`)
-> )
-> ;
Query OK, 0 rows affected (0.01 sec)
删除表
删除表t，整表删除；
mysql> drop table t;
Query OK, 0 rows affected (0.02 sec)
Part3:库基础操作
创建库
mysql> CREATE DATABASE helei DEFAULT CHARACTER SET utf8 COLLATE utf8_bin;
Query OK, 1 row affected (0.00 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| he1 |
| he3 |
| helei |
| maxscale |
| mysql |
| performance_schema |
| sys |
+--------------------+
8 rows in set (0.00 sec)
删除库
删除名为helei的库，注意，这一操作会删除掉helei库中所有的表；
mysql> drop database helei;
Query OK, 0 rows affected (0.00 sec)
1分钟系统级操作
Part1:启停数据库
[root@HE3 ~]# /etc/init.d/mysqld status
SUCCESS! MySQL running (3173)
[root@HE3 ~]# /etc/init.d/mysqld stop
Shutting down MySQL.... SUCCESS!
[root@HE3 ~]# /etc/init.d/mysqld start
Starting MySQL.. SUCCESS!
附录
Part1:常用SQL
创建和授权用户
CREATE USER 'helei'@'%' IDENTIFIED BY 'MANAGER';
GRANT SELECT,insert,update,delete ON *.* TO 'helei'@'%';
创建数据库：
CREATE DATABASE www CHARACTER SET utf8 COLLATE utf8_bin;
密码变更：
SET PASSWORD FOR 'root'@'localhost' = PASSWORD('MANAGER');
统计哪些ip连接
mysql> select substring_index(host,':', 1) from information_schema.processlist;
统计每个IP连接数：
mysql> select substring_index(host,":", 1) ip, count(*) from information_schema.processlist group by ip;
到库级别的ip连接数查看：
mysql> select db, substring_index(host,":", 1) ip, count(*) from information_schema.processlist group by db, ip;
查看当前连接数
mysql> show status like 'Threads%';
粗略统计每张表的大小
mysql> select table_schema,table_name,table_rows from tables order by table_rows desc;
要想知道每个数据库的大小的话，步骤如下：
1、进入information_schema 数据库（存放了其他的数据库的信息）
use information_schema;
2、查询所有数据的大小：
select concat(round(sum(data_length/1024/1024),2),'MB') as data from tables;
3、查看指定数据库的大小：
比如查看数据库home的大小
select concat(round(sum(data_length/1024/1024),2),'MB') as data from tables where table_schema='home';
4、查看指定数据库的某个表的大小
比如查看数据库home中 members 表的大小
select concat(round(sum(data_length/1024/1024),2),'MB') as data from tables where table_schema='home' and table_name='members';
无法更新或删除数据。可以通过设置FOREIGN_KEY_CHECKS变量来避免这种情况。
SET FOREIGN_KEY_CHECKS = 0;
删除完成后设置
SET FOREIGN_KEY_CHECKS = 1;
其他：
关闭唯一性校验
set unique_checks=0;
set unique_checks=1;
变更字符集
ALTER TABLE tbl_name CONVERT TO CHARACTER SET utf8;
添加主键
alter table `helei` add column `id` int(10) not null auto_increment primary key comment '主键' first; 但会锁表，先在测试库中测试时间，如果时间长，尝试利用pt工具
重命名表
alter table helei rename to helei_old;
锁表（用户退出则失效）
flush tables with read lock;unlock table;
锁某张表
lock tables helei read;
找出id是奇数和偶数
select * from t where id &1
select * from t where id=(id>>1)<<1
查看数据库已运行时间
show global status like 'uptime';
转自 http://suifu.blog.51cto.com/9167728/1870989?zk