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SELECT MP.*
FROM SurveyFrontend..WebResult WR
JOIN MeetingHistory MH
ON MH.WebResultID=WR.WebResultID
JOIN Meeting M
ON MH.MeetingID=M.MeetingID
JOIN MeetingPlanner MP
ON MP.MeetingPlannerID=M.MeetingPlannerID
WHERE PrimaryEntityID=2424
AND WR.TimeResultTaken>='1/1/2016'
AND CardSet=2
我查了一下,但找不到任何有關如何用多個連接完成外部連接的示例。我想拉上面的查詢完全相反。使用多個連接語句完成外部連接的邏輯是什麼?
我該怎麼做呢?
這正是我在尋找:
更新代碼:
SELECT MP.*
FROM SurveyFrontend..WebResult WR
FULL OUTER JOIN MeetingHistory MH
ON MH.WebResultID=WR.WebResultID
FULL OUTER JOIN Meeting M
ON MH.MeetingID=M.MeetingID
FULL OUTER JOIN MeetingPlanner MP
ON MP.MeetingPlannerID=M.MeetingPlannerID
WHERE PrimaryEntityID=2424
AND WR.TimeResultTaken>='1/1/2016'
AND CardSet=2
AND (MH.WebResultID IS NULL
OR MH.MeetingID IS NULL
OR MP.MeetingPlannerID IS NULL
OR WR.WebResultID IS NULL
OR M.MeetingID IS NULL
OR M.MeetingPlannerID IS NULL)
替換JOIN'這裏的'所有實例(其是隱含一個'INNER JOIN')與'FULL OUTER JOIN','WHERE'安亞鍵(一個或多個)是'NULL'或任何乙鍵是'NULL'。語法顯示在您裁剪的圖像中:http://www.codeproject.com/KB/database/Visual_SQL_Joins/Visual_SQL_JOINS_orig.jpg –
我知道這一部分,但我不知道要在WHERE子句中放置什麼。謝謝你! – juice
哦nvm,你編輯了你的評論。讓我試試看。 – juice