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The problem of joining tables in SQL

SELECT MID, FAD.FirstOpenedDate ,LCD.LastCloseDate
FROM mwMaster.dbo.Merchant M
JOIN        (
            SELECT MerchID, MIN(moddate) AS FirstOpenedDate
            FROM mwMaster.dbo.MerchantStatusHistory
            GROUP BY MerchID
            )   FAD ON FAD.MerchID = M.MerchID 
LEFT JOIN   (
            SELECT MerchID, MAX(moddate) AS LastCloseDate
            FROM mwMaster.dbo.MerchantStatusHistory
            GROUP BY MerchID
            )   LCD ON LCD.MerchID = M.MerchID
JOIN        (
            SELECT merchid ,avg(Transactions) ,avg(Profit) 
            FROM mwMaster.dbo.ResidualSummary RS
            WHERE RS.Date_Processed < LCD.LastCloseDate
            GROUP BY Merchid    
            )   R ON R.MerchID = M.MerchID

I am having trouble making the following connection. I ran into this problem and used temporary tables, but would like to know what I'm doing wrong. Basically, the line that does not work takes 3rd place. "<LCD.LastClostDate" says it cannot be connected. Is it possible to use the value from the LCD that I created in the subquery above (in this query I used table M in the same way, but I did not encounter any problem)? I think because the LCD table is dynamically created here, it cannot be used in a subquery, but this is just my guess.

Any ideas?

On the side of the note, I also saw people using CROSS and OVER. Not knowing how this works, but may be applicable here?

+5
2

, , , JOIN CROSS APPLY SQL 2005 +

SELECT MID, FAD.FirstOpenedDate ,LCD.LastCloseDate
FROM mwMaster.dbo.Merchant M
JOIN        (
            SELECT MerchID, MIN(moddate) AS FirstOpenedDate
            FROM mwMaster.dbo.MerchantStatusHistory
            GROUP BY MerchID
            )   FAD ON FAD.MerchID = M.MerchID 
LEFT JOIN   (
            SELECT MerchID, MAX(moddate) AS LastCloseDate
            FROM mwMaster.dbo.MerchantStatusHistory
            GROUP BY MerchID
            )   LCD ON LCD.MerchID = M.MerchID
CROSS APPLY(
        SELECT merchid ,avg(Transactions) ,avg(Profit) 
        FROM mwMaster.dbo.ResidualSummary RS
        WHERE RS.Date_Processed < LCD.LastCloseDate
        GROUP BY Merchid    
        )   R ON R.MerchID = M.MerchID

CTE

 WITH LCD AS (SELECT MerchID, MAX(moddate) AS LastCloseDate
        FROM mwMaster.dbo.MerchantStatusHistory
        GROUP BY MerchID),
  R AS (
              SELECT merchid ,avg(Transactions) ,avg(Profit) 
              FROM mwMaster.dbo.ResidualSummary RS
                   INNER JOIN LCD on 
                   LCD.MERCHID = RS.MERCHID
              WHERE RS.Date_Processed < LCD.LastCloseDate
              GROUP BY Merchid    
            )

SELECT MID, FAD.FirstOpenedDate ,LCD.LastCloseDate
FROM mwMaster.dbo.Merchant M
JOIN        (
            SELECT MerchID, MIN(moddate) AS FirstOpenedDate
            FROM mwMaster.dbo.MerchantStatusHistory
            GROUP BY MerchID
            )   FAD ON FAD.MerchID = M.MerchID 
LEFT JOIN LCD ON LCD.MerchID = M.MerchID
LEFT JOIN R ON R.MerchID = M.MerchID
+5

, :

SELECT MID,
       MIN(moddate) OVER (PARTITION BY MerchID) as FirstOpenedDate,
       MAX(moddate) OVER (PARTITION BY MerchID) as LastCloseDate
FROM mwMaster.dbo.Merchant
HAVING DateProcessed < LastCloseDate
+2

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