sql - 如果没有返回数据，如何返回带有 0 的行？

Question

我有一个查询，无论如何我都想显示行。如果返回了一些数据，查询将返回我需要的正确信息，但是在所有行都为空的情况下，我什么也没得到，显然，如果没有，我需要一行返回全 0，而不是什么都没有。

我试过使用 isnull()和 coalesce()考虑到这一点，但显然我做得不对。以下是我需要为此目的调整的基本查询。

SELECT
    Vendor
    ,SUM(TotalAssigned) as 'Total Production Assigned Not Completed'
    ,SUM(AssignedFees) as 'Work in process Fees'
    ,SUM(TotalSubmitted) as 'Total Production Submitted'
    ,SUM(SubmittedFees) as 'Submitted Production Fees'
FROM(
    SELECT
        distinct 
        v.ContactFirstName+' '+v.ContactLastName AS Vendor
        ,oi.orderid, oi.orderitemid
        ,CASE WHEN  oi.QueueID > 0 and oi.lastmilestoneid < 70 THEN 1 ELSE 0 END AS TotalAssigned
        ,CASE WHEN  oi.QueueID > 0 and oi.lastmilestoneid < 70 THEN dbo.GetAdjustedVendorFee(oi.OrderID, oi.OrderItemID) END AS AssignedFees
        ,CASE WHEN oim.MilestoneID = 70 THEN 1 ELSE 0 END AS TotalSubmitted
        ,CASE WHEN oim.MilestoneID = 70 THEN dbo.GetAdjustedVendorFee(oi.OrderID, oi.OrderItemID) END AS SubmittedFees

    FROM
    OrderItems oi
    LEFT JOIN OrderItemMilestones oim ON oim.OrderID = oi.OrderID and oim.OrderItemID = oi.OrderItemID
    LEFT JOIN Vendors v ON v.VendorID = oi.VendorID
    WHERE
    oim.MilestoneDate BETWEEN dbo.TruncateDate(dateadd(dd, -1, Current_Timestamp)) and dbo.TruncateDate(Current_Timestamp)
    and oi.VendorID in (105144) 
    and oi.productid not in (105)
)x

GROUP BY Vendor

Answer 1

一种方法是将表达式包装在 CTE 中，然后 UNION ALL它与
UNION ALL SELECT NULL, 0,0,0,0 WHERE NOT EXISTS(SELECT * FROM CTE)
例如

WITH CTE AS 
(SELECT
    Vendor
    ,SUM(TotalAssigned) as 'Total Production Assigned Not Completed'
    ,SUM(AssignedFees) as 'Work in process Fees'
    ,SUM(TotalSubmitted) as 'Total Production Submitted'
    ,SUM(SubmittedFees) as 'Submitted Production Fees'
FROM(
    SELECT
        distinct 
        v.ContactFirstName+' '+v.ContactLastName AS Vendor
        ,oi.orderid, oi.orderitemid
        ,CASE WHEN  oi.QueueID > 0 and oi.lastmilestoneid < 70 THEN 1 ELSE 0 END AS TotalAssigned
        ,CASE WHEN  oi.QueueID > 0 and oi.lastmilestoneid < 70 THEN dbo.GetAdjustedVendorFee(oi.OrderID, oi.OrderItemID) END AS AssignedFees
        ,CASE WHEN oim.MilestoneID = 70 THEN 1 ELSE 0 END AS TotalSubmitted
        ,CASE WHEN oim.MilestoneID = 70 THEN dbo.GetAdjustedVendorFee(oi.OrderID, oi.OrderItemID) END AS SubmittedFees

    FROM
    OrderItems oi
    LEFT JOIN OrderItemMilestones oim ON oim.OrderID = oi.OrderID and oim.OrderItemID = oi.OrderItemID
    LEFT JOIN Vendors v ON v.VendorID = oi.VendorID
    WHERE
    oim.MilestoneDate BETWEEN dbo.TruncateDate(dateadd(dd, -1, Current_Timestamp)) and dbo.TruncateDate(Current_Timestamp)
    and oi.VendorID in (105144) 
    and oi.productid not in (105)
)x

GROUP BY Vendor)
SELECT * FROM CTE
UNION ALL SELECT NULL, 0,0,0,0  WHERE NOT EXISTS(SELECT * FROM CTE)

这是a demo用一个不太复杂的语句