有两个表表一 AAA
种类mc 库存总量s1
A 997
B 1234表二 BBB
种类mc 出库数量s1
A 105
A 213
B 116
B 211
B 303
用一条SQL语句求出A,B各剩下多少?Select aaa.mc kind aaa.s1-(select sum(s1) from bbb where mc=aaa.mc) from aaa,bbb我写的这个SQL对不?
种类mc 库存总量s1
A 997
B 1234表二 BBB
种类mc 出库数量s1
A 105
A 213
B 116
B 211
B 303
用一条SQL语句求出A,B各剩下多少?Select aaa.mc kind aaa.s1-(select sum(s1) from bbb where mc=aaa.mc) from aaa,bbb我写的这个SQL对不?
from A join (
select mc,sum(sl) as sl
from B
group by mc) b
on a.mc=b.mc
from A join (
select mc,sum(sl) as sl
from B
group by mc) b
on a.mc=b.mc