我的SQL查询有问题 我有tableA:
productA priceA
P1 18
P2 35
P1 22
P2 19
还有tableB:
productB priceB
P1 3
P2 15
P1 80
P2 96
我希望结果是2个表中两个产品的总和。
product price
P1 123
P2 165
我想总结两张桌子的总和 我正在尝试这个查询,但这是错误的。
SELECT productA,
(SELECT SUM(priceA) FROM tableA GROUP BY productA),
(SELECT SUM(priceB) FROM tableB GROUP BY productB)
FROM tableA, tableB
WHERE productA = productB
GROUP BY productA
请帮帮我。
答案 0 :(得分:3)
您可以使用union
合并表格,并group by
使用结果:
select product
, sum(price)
from (
select productA as product
, priceA as price
from TableA
union all
select productB
, priceB
from TableB
) as SubQueryAlias
group by
product
答案 1 :(得分:1)
这实际上是总和的总和:
select
product,
sum(price)
from (
select productA as product, sum(priceA) as price from tableA group by 1
union all
select productB, sum(priceB) from tableB group by 1
)
group by 1
答案 2 :(得分:0)
由于联接似乎是解决此问题的一种自然方式,因此这是一个使用join
而不是union
的解决方案。它首先聚合子查询中的数据,然后将结果连接在一起:
select coalesce(a.productA, b.productB) as product,
coalesce(a.PriceA, 0) + coalesce(b.PriceB, 0) as price
from (select productA, sum(PriceA) as PriceA
from TableA
group by productA
) a full outer join
(select productB, sum(PriceB) as PriceB
from TableB
group by productB
) b
on a.productA = b.prodctB
我正在使用full outer join
,以防表格有不同的产品组。因此,我需要coalesce
语句中的select
。