Use a left hand value in right hand SQL comparison
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22-09-2019 - |
Question
I have this SELECT
statement:
SELECT SUM(dbo.DLData.Quantity)
FROM dbo.MasterDates
JOIN dbo.DLData ON MasterDates.[ID] = dbo.DLData.DownloadID
WHERE dbo.MasterDates.[Date] BETWEEN @From AND @To
AND dbo.MasterDates.SiteID = @X
If you plug in the @From
, @To
and @X
it works. This is to be the right hand side of a comparison. However in the comparison the @X
needs to come from the left hand side of the as the SELECT
on the outside is performing test on every SiteID
in the set. Without this clause the main clause works. They need to go together. Here is the full select statement with the above select left in. Eventually the two having clauses will determine the key products for a site.
--INSERT INTO SiteKeyProducts
SELECT dbo.MasterDates.SiteID as SiteID , dbo.DLData.Product as ProductID
FROM dbo.MasterDates
JOIN dbo.DLData ON dbo.MasterDates.[ID] = dbo.DLData.DownloadID
WHERE dbo.MasterDates.[Date] BETWEEN @From AND @To
GROUP BY dbo.MasterDates.SiteID , dbo.DLData.Product
HAVING
SUM(dbo.DLData.Quantity) > 960 OR
SUM(dbo.DLData.Quantity) > (SELECT SUM(dbo.DLData.Quantity)
FROM dbo.MasterDates
JOIN dbo.DLData ON MasterDates.[ID] = dbo.DLData.DownloadID
WHERE dbo.MasterDates.[Date] BETWEEN @From AND @To
AND dbo.MasterDates.SiteID = @X)
ORDER BY dbo.MasterDates.SiteID
How do you use the outer clause on an inner statement? Hell, I don't even know if I am using the correct terminology to describe my problem.
Arrgghh - Set based logic does my head in!!
Solution 2
Matt Whitfield on the ask.sqlservercentral StackExchange site came up with the following answer to this problem:
SELECT outerMaster.SiteID as SiteID , dbo.DLData.Product as ProductID
FROM dbo.MasterDates outerMaster
JOIN dbo.DLData ON outerMaster.[ID] = dbo.DLData.DownloadID
WHERE outerMaster.[Date] BETWEEN @From AND @To
GROUP BY outerMaster.SiteID , dbo.DLData.Product
HAVING
SUM(dbo.DLData.Quantity) > 960 OR
SUM(dbo.DLData.Quantity) > (SELECT SUM(dbo.DLData.Quantity)
FROM dbo.MasterDates innerMaster
JOIN dbo.DLData ON innerMaster.[ID] = dbo.DLData.DownloadID
WHERE innerMaster.[Date] BETWEEN @From AND @To
AND innerMaster.SiteID = outerMaster.SiteID)
ORDER BY outerMaster.SiteID
And RickD came up with this answer on the ask.sqlteam.com site:
--INSERT INTO SiteKeyProducts
SELECT
MD.SiteID as SiteID ,
DLD.Product as ProductID
FROM dbo.MasterDates MD
JOIN dbo.DLData DLD
ON MD.[ID] = DLD.DownloadID
LEFT JOIN (SELECT SiteID,
SUM(dbo.DLData.Quantity) SumMDQuantity
FROM dbo.MasterDates
JOIN dbo.DLData ON MasterDates.[ID] = dbo.DLData.DownloadID
WHERE dbo.MasterDates.[Date] BETWEEN @From AND @To
GROUP BY SiteID) as sumMD
ON sumMD.SiteID = MD.SiteID
WHERE MD.[Date] BETWEEN @From AND @To
GROUP BY MD.SiteID , DLD.Product
HAVING
SUM(DLD.Quantity) > 960 OR
SUM(DLD.Quantity) > sumMD.SumMDQuantity
ORDER BY MD.SiteID
Both work great, though Matts bests Ricks effort despite my initial view that a Join would be faster. Matts takes ~2m 10s while Ricks takes ~2m 40s. This is for the largest live database as both takes less than 10s on the test db.
OTHER TIPS
I think you want to join this subquery, not use it in a having statement
SELECT SUM(dbo.DLData.Quantity)
FROM dbo.MasterDates
JOIN dbo.DLData ON MasterDates.[ID] = dbo.DLData.DownloadID
WHERE dbo.MasterDates.[Date] BETWEEN @From AND @To
AND dbo.MasterDates.SiteID = @X