SQL语句---Select

来源：百度知道编辑：UC知道时间：2024/05/04 08:50:17

表T1中的字段及数据如下
name1（货名） S1（货的总量）
a 2000
b 1600
表T2中的字段及数据如下
name2 S1（卖出的货量）
a 200
b 150
a 300
a 100
b 200
请用一条SQL语句，查询a,b还剩下多少货？（一条语句实现）

select T1.name1,T1.s1-(select sum(T2.s1) from T2 where T2.name2=T1.name1) as s1 from T1
可以直接运行

select T1.name1,T1.a-(select sum(T2.s1) from T2 where T2.name2=T1.name1) as s1 from T1

select m.name1,m.s1-n.digit from t1 m
left join (select name2,sum(isnull(s1,0)) as digit from t2 group by name2) n
on m.name1=n.name2

select t1.name1,t1.s1-t2.s1 as cha
from t1,(select name2,sum(s1) s1 from t2 group by 1) t3
where t1.name1=t3.name2

select t1.name1, sum(t1.s1)-sum(t2.s1) from t1,t2 where t1.name1=t2.name2 group by t1.name1, t2.name2