Mysql基础语法

mysql

SELECT VERSION(), CURRENT_DATE, now();
select user();

create database pets;
show databases;

use pets;

CREATE TABLE cats
(
id INT unsigned NOT NULL AUTO_INCREMENT, # Unique ID for the record
name VARCHAR(150) NOT NULL, # Name of the cat
owner VARCHAR(150) NOT NULL, # Owner of the cat
birth DATE NOT NULL, # Birthday of the cat
PRIMARY KEY (id) # Make the id the primary key
);
show tables;

describe cats; desc

INSERT INTO cats ( name, owner, birth) VALUES
( 'Sandy', 'Lennon', '2015-01-03' ),
( 'Cookie', 'Casey', '2013-11-13' ),
( 'Charlie', 'River', '2016-05-21' );

SELECT * FROM cats;

增加/删除/修改列：

alter table cats add gender char(1) [after name];
alter table cats drop gender;

alter table cats change name name_new char(30);

alter table cats modify name char(10);

alter table cats alter age set default 10;

alter table cats alter age drop default;

alter table cats rename to cats_t;

查看用户权限：

SHOW GRANTS FOR 'admin'@'localhost';

日期计算
http://dev.mysql.com/doc/refman/5.7/en/date-calculations.html

自定义变量
mysql> SELECT @min_price:=MIN(price),@max_price:=MAX(price) FROM shop;
mysql> SELECT * FROM shop WHERE price=@min_price OR price=@max_price;

自增列：
CREATE TABLE animals (
id MEDIUMINT NOT NULL AUTO_INCREMENT,
name CHAR(30) NOT NULL,
PRIMARY KEY (id)
);
INSERT INTO animals (name) VALUES ('dog'),('cat'),('penguin'),('lax'),('whale'),('ostrich');

更新列：

update user set age =age+1 where id=1;