如何在不加入三个表的情况下获得结果

Question

我有像

这样的SQL连接

select B.Team,Sum(A.Quota) as Quota from TableA A 
inner join TableB B on B.code = A.TblCode
group by B.Team

给我结果

团队配额

备用5000

Grace 2000

我有另一个像

这样的SQL连接

select B.Team, Sum(C.Revenue) As Revenue from TableC C
inner join TableB B on B.code = c.StaCode
group by B.Team

以上sql的结果是

团队收入

备用10000

Grace 12000

除了加入三个表之外，是否可以得到如下所示的结果？

团队配额收入

备用5000 10000

Grace 2000 12000

我尝试连接三个表，这给了我不同的结果，因为其中一个表中有重复项。

Answer 1

你可以JOIN这两个结果

SELECT x.Team, X.Quota, Y.Revenue
FROM (select B.Team, Sum(A.Quota) as Quota 
      from TableA A 
          inner join TableB B on B.code = A.TblCode
      group by B.Team) as x
JOIN (select B.Team, Sum(C.Revenue) As Revenue 
      from TableC C
          inner join TableB B on B.code = c.StaCode
      group by B.Team) as Y ON X.Team = Y.Team

Answer 2

您可以使用相关子查询分别计算值：

SELECT Team,
       (SELECT SUM(Quota)
        FROM TableA
        WHERE TblCode = TableB.code) AS Quota,
       (SELECT SUM(Revenue)
        FROM TableC
        WHERE StaCode = TableB.code) AS Revenue
FROM TableB

（这相当于LEFT JOIN，但我怀疑如果另一个没有匹配，你想要删除一个配额/收入值。）