For what it's worth, here's my opinion on Tuning Advisor.
If you put sugar on dog food it may taste better but do you really want to eat it?
The meaning of course is that adding a covering index to a poor performing query may make it run faster, but you're better advised to get your query running at optimal performance without using an index first. Then if it still needs to be faster, see what Tuning Advisor recommends.
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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