I want to select the Last 10 Average Weights - sql

Question

Below is my query but when I include my CapturedDateTime and IsOutOfSpec columns then it returns multiple rows but I only want one record to be returned that displays the averages of the last 10 records. So it must return the average PartWeight, average SprueWeight and average Bom Weight for a specified stock code.
--Last 10 Average Report
SELECT Top 10 c.StockCode,i.LongDesc,
AVG(c.PartWeightGram) AS 'Part Weight Average',
AVG(c.SprueWeightGram) AS 'Sprue Weight Average' ,
AVG(c.TolerancePercentage) AS 'Tolerance Average' ,
AVG(c.BomWeightKG * 1000) AS 'Bom Weight Average' ,
AVG(c.PartWeightGram + (c.SprueWeightGram / 2)) - (c.BomWeightKG) AS 'Variance To Syspro Average',
AVG((((((c.PartWeightGram + c.SprueWeightGram / 2))) - (c.BomWeightKG * 1000)) / (c.BomWeightKG * 1000)) * 100) AS 'VarianceToSysproPct'
FROM tblComponentWeightCheck c
LEFT JOIN [Mercury].[EncoreCompanyA].dbo.InvMaster i ON c.StockCode = i.StockCode
WHERE c.StockCode='000-256966-020' And Deleted = 'False'
GROUP BY c.StockCode,i.LongDesc,c.BomWeightKG
ORDER BY c.StockCode DESC
This is my Table:
SELECT [ComponentWeightCheckID]
,[EmpID]
,[StockCode]
,[Process]
,[PartWeightGram]
,[SprueWeightGram]
,[BomWeightKG]
,[TolerancePercentage]
,[AssetID]
,[CapturedDateTime]
,[Hostname]
,[Username]
,[IsOutOfSpec]
,[Tool]
,[Deleted]
FROM [dbo].[tblComponentWeightCheck]
Sample Data:
SELECT Top 10 c.StockCode,i.LongDesc AS 'Description',
(SELECT TOP 10 AVG(PartWeightGram) FROM tblComponentWeightCheck c WHERE c.StockCode = '000-256966-020' GROUP BY c.StockCode ) AS 'Part Weight Average',
(SELECT TOP 10 AVG([SprueWeightGram]) FROM tblComponentWeightCheck c WHERE c.StockCode = '000-256966-020' GROUP BY c.StockCode ) AS 'Sprue Weight Average',
(SELECT TOP 10 AVG(c.TolerancePercentage) FROM tblComponentWeightCheck c WHERE c.StockCode = '000-256966-020' GROUP BY c.StockCode ) AS 'Tolerance Average',
(SELECT TOP 10 AVG([BomWeightKG]) FROM tblComponentWeightCheck c WHERE c.StockCode = '000-256966-020' GROUP BY c.StockCode ) AS 'Bom Weight Average',
(SELECT TOP 10 AVG((c.PartWeightGram + (c.SprueWeightGram / 2)) - (c.BomWeightKG * 1000)) FROM tblComponentWeightCheck c WHERE c.StockCode = '000-256966-020' GROUP BY c.StockCode ) AS 'Variance To Syspro Average',
(SELECT TOP 10 AVG((((((c.PartWeightGram + c.SprueWeightGram / 2))) - (c.BomWeightKG * 1000)) / (c.BomWeightKG * 1000)) * 100) FROM tblComponentWeightCheck c WHERE c.StockCode = '000-256966-020' GROUP BY c.StockCode ) AS 'Variance To Syspro & Average'
FROM tblComponentWeightCheck c
LEFT JOIN [Mercury].[EncoreCompanyA].dbo.InvMaster i ON c.StockCode = i.StockCode
WHERE c.StockCode = '000-256966-020'
AND CONVERT(Date, c.CapturedDateTime) Between '2021-04-01' AND '2021-05-24'
GROUP BY c.StockCode, i.LongDesc
This image shows the result of the above query.It only returns 1 row which it should but it is missing my CapturedDateTime AND IsOutOfSpec columns, as soon as i include those then it returns multiple records which i don't want

Answer 1

Presumably, the LEFT JOIN is not needed -- it would seem odd to have stock codes that are not in the inventory master.
You can do this pretty easily using APPLY:
SELECT Top 10 i.StockCode, i.LongDesc,
AVG(c.PartWeightGram) AS Part_Weight_Average,
AVG(c.SprueWeightGram) AS Sprue_Weight_Average,
AVG(c.TolerancePercentage) AS Tolerance_Average,
AVG(c.BomWeightKG * 1000) AS Bom_Weight_Average,
AVG(c.PartWeightGram + (c.SprueWeightGram / 2)) - (c.BomWeightKG) AS Variance_To_Syspro_Average,
AVG((((((c.PartWeightGram + c.SprueWeightGram / 2))) - (c.BomWeightKG * 1000)) / (c.BomWeightKG * 1000)) * 100) AS VarianceToSysproPct
FROM [Mercury].[EncoreCompanyA].dbo.InvMaster i CROSS APPLY
(SELECT TOP (10) c.*
FROM tblComponentWeightCheck c
WHERE c.StockCode = i.StockCode
ORDER BY c.CapturedDateTime DESC
) c
WHERE i.StockCode = '000-256966-020' AND Deleted = 'False'
GROUP BY i.StockCode, i.LongDesc, c.BomWeightKG
ORDER BY i.StockCode DESC;
For performance, I recommend indexes on tblComponentWeightCheck(StockCode, CapturedDateTime DESC) and InvMaster(StockCode).

Answer 2

Judging by your query, you should use a window function and a subquery instead of top 10. Following an example. However, you will have to provide the sorting criteria for the ROW_NUMBER() in order to define your "TOP 10"...
--Last 10 Average Report
SELECT c.StockCode,c.LongDesc,
AVG(c.PartWeightGram) AS 'Part Weight Average',
AVG(c.SprueWeightGram) AS 'Sprue Weight Average' ,
AVG(c.TolerancePercentage) AS 'Tolerance Average' ,
AVG(c.BomWeightKG * 1000) AS 'Bom Weight Average' ,
AVG(c.PartWeightGram + (c.SprueWeightGram / 2)) - (c.BomWeightKG) AS 'Variance To Syspro Average',
AVG((((((c.PartWeightGram + c.SprueWeightGram / 2))) - (c.BomWeightKG * 1000)) / (c.BomWeightKG * 1000)) * 100) AS 'VarianceToSysproPct'
FROM (
SELECT c.StockCode
,i.LongDesc
,c.PartWeightGram
,c.SprueWeightGram
,c.TolerancePercentage
,c.BomWeightKG
,c.PartWeightGram
,c.PartWeightGram
,ROW_NUMBER() OVER (PARTITION BY c.StockCode ORDER BY ...) AS rn
FROM tblComponentWeightCheck c
LEFT JOIN [Mercury].[EncoreCompanyA].dbo.InvMaster i ON c.StockCode = i.StockCode
WHERE Deleted = 'False'
) c
WHERE c.StockCode='000-256966-020'
AND rn <= 10
GROUP BY c.StockCode,c.LongDesc,c.BomWeightKG
ORDER BY c.StockCode DESC