Query Tricks Which Don’t Trick

Gail Shaw has a follow-up with more query “tricks” that aren’t fooling anyone:

In a similar vein to last week’s blog post… I heard an interesting comment recently. “Change that Column != 2 to a Column > 2 or Column < 2 combination, it can use indexes better.”

Sounds like something that clearly needs testing!

Not shockingly, this did nothing to make the query run faster or use fewer resources.  There are ways to rewrite queries to improve performance while maintaining the same result structure (a common example being rewriting query using a cursor or WHILE loop to perform one set-based operation), but Gail’s point is vital:  test your changes and make sure that if you’re saying it will perform better, that it actually perform better.

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