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
启动
$: mysql.server start
关闭
$:mysql.server stop
连接
$:mysql -u root -p
检查mysql进程
ps -ef | grep mysqld
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
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
查看数据库
mysql> show databases;
使用test数据库
mysql> use test
查看表
mysql> show tables;
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));
插入数据
mysql> insert into person value (null,'hao','jery',13,1,'beijing');
删除一行数据
mysql> delete from person where id = 4;
查询去重
mysql> select distinct lastname from person;
where
mysql> select * from person where address = 'beijing';
and
mysql> select * from person where age>13 and age<26;
or
mysql> select * from person where age<20 or age >25;
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
update
mysql> update person set lastname='zhuxiaoxiao' where lastname='du';
mysql> update person set lastname='update',age=27 where id = 12;
delete
mysql> delete from person where lastname ='zhixiang';