Another Interview Question

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One question I ask when interviewing is what types of T-SQL statements are the worst for performance, I am looking for answers like the below (not in any order):

  • Cursors
  • IN clauses
  • Large INNER JOINs

What this tells me about the person is that they are conscience of the code impact they have on the server.  Someone that doesn't know the answer will write anything that works just to get their job done -- which means that I will later have to clean-up their stuff.

{6230289B-5BEE-409e-932A-2F01FA407A92}

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