不同表中的总和之和

Question

我有SQL查询的问题.
我有桌子A:

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个表中的两个产品的总和.

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

请帮我.

Answer 1

您可以使用 aunion来合并表，并group by在结果上：

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