日期:2014-05-17  浏览次数:20469 次

求一条两个表的查询语句
第一个表
id name
1 li
2 wang
3 li
4 zhao
第二个表
id inout num
1 0 100
1 0 50
1 1 100
1 1 200
2 0 100
2 0 100
2 1 50
2 1 50
3 0 100
3 0 200
3 1 100
3 1 50
利用两个表查询,结果如下
id name num0 num1
1 li 150 300
2 wang 200 100
3 li 300 150
4 zhao 0 0
其中num0为同一id下inout=0之和,num1为同一id下inout=1之和,表一中id为主键,表一有几个记录,查询结果就有几个记录

------解决方案--------------------
SQL code

select id,name,
       (select sum(num) from tab2 b ,tab1 a where a.id=b.id and inout='0')as num0,
       (select sum(num) from tab2 b ,tab1 a where a.id=b.id and inout='1')as num1
from  tab1 a ,tab2 b 
where a.id=b.id
group id,name

------解决方案--------------------
SQL code
declare @t1 table(id int,name varchar(10))
insert into @t1
select 1, 'li' union all
select 2, 'wang' union all
select 3, 'li' union all
select 4, 'zhao'

declare @t2 table(id int,inout int,num int)
insert into @t2
select 1, 0, 100 union all
select 1, 0, 50 union all
select 1, 1, 100 union all
select 1, 1, 200 union all
select 2, 0, 100 union all
select 2, 0, 100 union all
select 2, 1, 50 union all
select 2, 1, 50 union all
select 3, 0, 100 union all
select 3, 0, 200 union all
select 3, 1, 100 union all
select 3, 1, 50

select a.id,
    a.name,
    sum(case when b.inout=0 then b.num else 0 end) num0,
    sum(case when b.inout=1 then b.num else 0 end) num1 from @t1 a
left join @t2 b
on a.id=b.id
group by a.id,a.name

/*
id          name       num0        num1
----------- ---------- ----------- -----------
1           li         150         300
3           li         300         150
2           wang       200         100
4           zhao       0           0
*/