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mysql的子查询

select id,name,age,sex,punch1from test0where id in --等号改成in(select id from test1where flag = 0 );

我做了测试(select admin_type from cool_admin where admin_name ='admin')的结果是id 但是select (select admin_type from cool_admin where admin_name ='admin') from `tk_team` left join tk_user using(id)的结果为: select id from `tk_t...

不能先select出同一表中的某些值,再update这个表(在同一语句中) 解决方案 --1.把需要删除的数据放到另外的一张表里create table table_test as select oneName from one group by OneName,OneAge,oneSex,oneAddress having count(oneName) > 1;...

update film set f_price=(select f_price*2 from film where f_id=5) where f_actor='甄子丹';

where后加多个条件可以用and来连接。 如,student表中有如下数据: 现在要查,sex为男,age为20的那些数据,可用如下语句: 1 select * from student where sex='男' and age=20; 结果截图:

mysql 删除可以用子查询。 mysql删除子查询中的记录语句: Sql代码 delete from t_5star where locationid in ( select e.locationid from ( select a.* from t_5star as a , t_als_data as b where a.term = b.term ) e ) 关键是子查询中的语句...

1、where型子查询 (把内层查询结果当作外层查询的比较条件) #不用order by 来查询最新的商品 select goods_id,goods_name from goods where goods_id = (select max(goods_id) from goods); #取出每个栏目下最新的产品(goods_id唯一) select ...

select T2.C from T2 where Exists(select * from T1,T3 where T1.B=T2.B and T2.C=T3.C and D='value'); 你想输出C的话,主查询里from T2或T3都可以。

不懂你为什么这样写,你可以试试下面的方法,根据需求可以left/right join。 Select Count(1) From a,b where a.proid=b.id

举个例子: DELIMITER $$ CREATE DEFINER=`root`@`localhost` PROCEDURE `Select_bad`() BEGIN select id,name,age,sex,punch1 from test0 where id = ( select id from test1 where flag = 0 ); END 查询语句: select id,name,age,sex,punch1 ...

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