背景
最近常参与后台php项目，虽说刚毕业时自学过一阵子php和mysql，不过长时间没用也忘差不多了，于是把mysql再温习一遍，前端同学也可以一起学习下！
mysql安装以及操作
安装
brew install mysql
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启动
$: mysql.server start
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关闭
$:mysql.server stop
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连接
$:mysql -u root -p
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检查mysql进程
ps -ef | grep mysqld
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问题
重启mysql提示MySQL server PID file could not be found!
1. ps -ef|grep mysqld
2. kill -9 进程号
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DML&DDL
数据操作语言DML
- select
- update
- delete
- insert into
数据定义语言DDL
- crate database
- alter database
- create table
- alter table
- drop table
- crate index
- drop index
SQL
基础操作
创建数据库
mysql> create database test
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查看数据库
mysql> show databases;
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使用test数据库
mysql> use test
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查看表
mysql> show tables;
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一，基础教程
创建表
mysql> create table person (id int(4) not null primary key auto_increment,lastname varchar(20) not null,firstname varchar(20),age int(4),sex int(4) not null,address varchar(20));
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插入数据
mysql> insert into person value (null,'hao','jery',13,1,'beijing');
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删除一行数据
mysql> delete from person where id = 4;
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查询去重
mysql> select distinct lastname from person;
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where
mysql> select * from person where address = 'beijing';
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and
mysql> select * from person where age>13 and age<26;
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or
mysql> select * from person where age<20 or age >25;
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order by
mysql> select * from person order by age;
mysql> select lastname,age from person order by age;
mysql> select lastname,age from person order by age asc; //顺序显示
mysql> select lastname,age from person order by age desc;//逆向显示
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update
mysql> update person set lastname='zhuxiaoxiao' where lastname='du';
mysql> update person set lastname='update',age=27 where id = 12;
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delete
mysql> delete from person where lastname ='zhixiang';
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