So you've posted DDL which is a good start:
vignesh.ms (1/17/2014)
this is the sample table
create table #sample(
Productid varchar(10),
purchasedate datetime,
customerid varchar(100)
);
And expected output in the pretty table you posted. Now how about some consumable sample data to populate the #sample table with?
I'm thinking this is not a gaps problem at all. Rather it is a problem that can be solved with a window frame.
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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