mysql 常用命令(一)

1. 函数向日期添加指定的时间间隔

DATE_ADD(date,INTERVAL expr type)
eg:DATE_ADD(CURDATE(),INTERVAL 1 MONTH) //在当前时间加一个月

2.计算年龄

eg:select birth ,CURDATE, YEAR(CURDATE())-YEAR(birth) - (RIGHT(MONTH(CURDATE),) < RIGHT(MONTH(birth),5)) as age from pet;

birth                  CURDATE         age

1998-09-11       2003-08-19      4

YEAR() 获取年,MONTH() 获取月,day() 获取天

3.拥有某个列的最大值的行

eg:SELECT article, dealer, price FROM  shop WHERE  price=(SELECT MAX(price) FROM shop);

eg:SELECT article, dealer, price FROM shop ORDER BY price DESC LIMIT 1;(假设有多个最大价格,那这个语句只能查找出一个

 

 

posted @ 2016-12-17 13:36  桔子木木  阅读(209)  评论(0编辑  收藏  举报