如何在where子句中過濾組合鍵？

Question

我正在嘗試使用組合鍵來過濾查詢，但是，我不確定如何在where子句中使用復合鍵來過濾查詢。 XSiteProductItemId和MercuryProductItemId組成一個標識唯一行的復合鍵。

這是我的查詢：

SELECT VMPOrdersExtract.XSiteProductItemId
  ,  VMPOrdersExtract.MercuryProductItemId
FROM Appraisal.ext.VMPOrders AS VMPOrdersExtract
LEFT JOIN dw.DimAppraisal DimApprasial ON DimApprasial.XsiteProductItemId = VMPOrdersExtract.XSiteProductItemId
  AND DimApprasial.MercuryProductItemId = VMPOrdersExtract.MercuryProductItemId
WHERE VMPOrdersExtract.LastSyncDateTime > DimApprasial.LastSyncDateTime
OR (
    VMPOrdersExtract.XSiteProductItemId
    AND VMPOrdersExtract.MercuryProductItemId
) is null

顯然，我在WHERE子句中的OR條件在語法上是錯誤的。 如何僅過濾在DimAppraisal表中為null或不存在的組合鍵記錄？

Answer 1

怎么樣

WHERE VMPOrdersExtract.LastSyncDateTime > DimApprasial.LastSyncDateTime
OR (VMPOrdersExtract.XSiteProductItemId IS NULL AND 
VMPOrdersExtract.MercuryProductItemId IS NULL);

Answer 2

也將其添加到答案中；）

 SELECT VMPOrdersExtract.XSiteProductItemId, VMPOrdersExtract.MercuryProductItemId 
FROM Appraisal.ext.VMPOrders AS VMPOrdersExtract LEFT JOIN dw.DimAppraisal DimApprasial 
ON DimApprasial.XsiteProductItemId = VMPOrdersExtract.XSiteProductItemId AND 
DimApprasial.MercuryProductItemId = VMPOrdersExtract.MercuryProductItemId WHERE 
VMPOrdersExtract.LastSyncDateTime > DimApprasial.LastSyncDateTime OR 
(VMPOrdersExtract.XSiteProductItemId is null AND VMPOrdersExtract.MercuryProductItemId is null)