sql server - is "NOT EXISTS" bad SQL practice? -

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in sql server, using "not exists" in queries considered bad practice , i've heard microsoft code reviews test not exists , flag these warnings. why not exists considered bad practice , join operators preferred on not exists?

given that:

  • any reasonably query optimizer able convert between “not exists”, “exists” , "joins", there no performance difference these days.

  • “not exists” can easier read joins.

therefore don’t consider “not exists” bad practice in general case.


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