Question

我正在尝试获取所有id_user的列表以及creditRecieved的数量和creditUsed的数量，我实际上想添加第三个选项，如果有的话，提到左边的。如果creditReceived更大，则信用额度更高。但是第一部分现在输出加倍，所以我开始在StackOverflow上进行解释，但是我无法让它工作。

SELECT 
    dbo.UserPurchase.CreditUsed,
    dbo.UserCredit.CreditRecieved

FROM
(
    SELECT SUM(dbo.UserPurchase.creditUsed) AS CreditUsed
    FROM dbo.UserPurchase
)

dbo.UserPurchase LEFT JOIN

(
    SELECT SUM(dbo.UserCredit.creditRecieved) AS CreditRecieved
    FROM dbo.UserCredit
)

dbo.UserCredit ON dbo.UserPurchase.id_user = dbo.UserCredit.id_user

数据来自这两个表

表dbo.UserCredit

id          id_user     creditRecieved PurchasePrice
----------- ----------- -------------- -------------
1           1           150            750
2           1           25             100
3           2           65             15

表dbo.UserPurchase

id          id_user     creditUsed  date
----------- ----------- ----------- -----------
1           1           175         NULL
2           2           3           NULL
3           2           2           NULL

我想得到以下结果

id_user     CreditRecieved CreditUsed  CreditLeftOver
----------- -------------- ----------- --------------
1           175            175         0
2           65             5           60

Answer 1

如果我理解正确，你想要id_user总结的creditUsed和creditRecieved（你最后的错字？）？这将是查询：

SELECT p.id_user, SUM(p.creditUsed), SUM(u.creditRecieved)
  FROM dbo.UserCredit u
  LEFT JOIN dbo.UserPurchase p ON p.id_user = u.id_user
 GROUP BY p.id_user

Answer 2

尝试分别查询每个表：

IFooBar

请注意，SELECT users.id_user, coalesce(credit.received, 0) received, coalesce(purchase.used, 0) Used, coalesce(credit.received, 0) - coalesce(purchase.used, 0) LeftOver, coalesce(purchase.purchaseCount, 0) purchaseCount FROM ( select distinct id_user from dbo.UserCredit union select distinct id_user from dbo.UserPurchase ) users left outer join ( select id_user, sum(creditRecieved) received from dbo.UserCredit group by id_user ) credit on users.id_user = credit.id_user left outer join ( select id_user, sum(creditUsed) used, count(1) purchaseCount from dbo.UserPurchase group by id_user ) purchase on users.id_user = purchase.id_user中存在拼写错误。它应该是CreditRecieved。

Answer 3

您可以使用此查询

SELECT 
    C.id_user,
    C.CreditRecieved,
    P.CreditUsed,
    C.CreditRecieved - P.CreditUsed CreditLeftOver
FROM 
    (SELECT id_user, SUM(creditRecieved) CreditRecieved FROM UserCredit GROUP BY id_user) C 
    LEFT JOIN
    (SELECT id_user, SUM(creditUsed) CreditUsed FROM UserPurchase GROUP BY id_user) P ON C.id_user = P.id_user

T-SQL（Azure）表提供双重结果

3 个答案: