sql-server-2008 - 试图弄清楚如何在 SQL 中构建查询

Question

我在构建查询时遇到了一些麻烦，我需要从 FamilyAccountDetails 表中返回 AccountID，其中家庭帐户至少有一个孩子（一个孩子是 AccountDetails.AccountID 等于 FamilyAccountDetails.AccountID），其 HoldFlag = 0。

AccountDetails
EntID  |HoldFlag|AccountID|StatusFlag

FamilyAccountDetails
EntID|FamilyAccountID|AccountID|StatusFlag

SQL：

      Select FD.AccountID, FD.FamilyAccountId 
from Test2TMAdvisor5.dbo.FamilyAccountDetails FD
      where FD.EnterpriseId = 'TestDan'
      and AccountId in (Select AccountId from Test2TMAdvisor5.dbo.AccountDetails AD where Ad.AccountID = FD.AccountId and ad.HoldFlag =0)

Answer 1

SELECT
    FD.[AccountID]
    ,FD.[FamilyAccountId] 
FROM
    FamilyAccountDetails FD
WHERE
    FD.[EnterpriseId] = 'TestDan'
    AND EXISTS 
        (
        SELECT 
            * 
        FROM 
            AccountDetails AD
        WHERE 
            AD.[AccountID] = FD.[AccountId] 
            AND AD.[HoldFlag] = 0
        )

Answer 2

此 SQL 查询应提取您想要的结果：

SELECT
    FD.[AccountID]
    ,FD.[FamilyAccountId] 
FROM
    FamilyAccountDetails FD
INNER JOIN AccountDetails AD on AD.[AccountID] = FD.[AccountId] 
WHERE
    FD.EntID = 'TestDan'
    AND AD.[HoldFlag] = 0