This query will get you the output you requested but I'm sure it is way over-simplified.
SELECT invoice_no
,item_no=MAX(CASE WHEN item_type <> 'K' THEN item_no END)
,sales=SUM(CASE WHEN item_type = 'K' THEN invoice_qty END)
,free=SUM(CASE WHEN item_type <> 'K' THEN invoice_qty END)
-SUM(CASE WHEN item_type = 'K' THEN invoice_qty END)
FROM nh
GROUP BY invoice_no;
For example, what happens when you have an invoice with multiple kits?
My thought question: Have you ever been told that your query runs too fast?
My advice:
INDEXing a poor-performing query is like putting sugar on cat food. Yeah, it probably tastes better but are you sure you want to eat it?
The path of least resistance can be a slippery slope. Take care that fixing your fixes of fixes doesn't snowball and end up costing you more than fixing the root cause would have in the first place.
Need to UNPIVOT? Why not CROSS APPLY VALUES instead?[/url]
Since random numbers are too important to be left to chance, let's generate some![/url]
Learn to understand recursive CTEs by example.[/url]
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