Jeff Moden (10/3/2012)
Jason-299789 (10/3/2012)
Karthick,Jeff was making valid point about about how to create the Tally table in the first place, most people will write a while loop, or a recursive CTE rather than using a cross join between two of the sys tables in the db.
I suspect Jeff wants to see the developer do the cross join rather than the CTE or a While loop. 😀
Or a cascading cross-joined CTE Itzik Ben-Gan style. Or a SELECT from a Tally table.
Bonus points if the Developer says, "It Depends" and then demonstrates and explains all 3 without further prompting. Even more points for the tangent of using IDENTITY vs ISNULL(ROW_NUMBER()) on the creation of a physical Tally Table.
I think I'd get 3 out of 4. What's that last bit about?
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]
[url url=http://www.sqlservercentral.com/articles/St