mysql 简单的查询语句select

下面是简单实用的查询语句select例子:

表名:zc36

`id` int(11) NOT NULL auto_increment, //字段id,递增

`num` int(11) NOT NULL, //数量

`title` varchar(50) NOT NULL, //标题

PRIMARY KEY (`id`) //id 为主键

绝对相等查询(如查询的是域名为'zc36.net'的记录):

SELECT * FROM `zc36` WHERE title='zc36.net'

查询开头是"zc36的例子:

select * from zc36 where title like 'zc36%'

查询结尾是"zc36的例子:

select * from zc36 where title like '%zc36'

查询包含"zc36的例子:

select * from zc36 where title like '%zc36%'

取出多少条的语句例子:

select * from zc36 where num>10 order by num desc limit 2

*num大于10的并取出num最大的两条,desc是按递减排序,asc是递培排序

查询总的条数的例子:

select count(id) from zc36

查询num的汇总数量的例子:

SELECT sum( num ) FROM `zc36

查询num的平均数的例子:

SELECT avg( num ) FROM `zc36`

如有什么问题请在下面回复,本站点是:

简单的查询语句select例子:

表名:zc36

`id` int(11) NOT NULL auto_increment, //字段id,递增

`num` int(11) NOT NULL, //数量

`title` varchar(50) NOT NULL, //标题

PRIMARY KEY (`id`) //id 为主键

绝对相等查询(如查询的是域名为'zc36.net'的记录):

SELECT * FROM `zc36` WHERE title='zc36.net'

查询开头是"zc36的例子:

select * from zc36 where title like 'zc36%'

查询结尾是"zc36的例子:

select * from zc36 where title like '%zc36'

查询包含"zc36的例子:

select * from zc36 where title like '%zc36%'

取出多少条的语句例子:

select * from zc36 where num>10 order by num desc limit 2

*num大于10的并取出num最大的两条,desc是按递减排序,asc是递培排序

查询总的条数的例子:

select count(id) from zc36

查询num的汇总数量的例子:

SELECT sum( num ) FROM `zc36

查询num的平均数的例子:

SELECT avg( num ) FROM `zc36`

如有什么问题请在下面回复,本站是http://www.zc36.net