MyDoggieJessie (8/30/2013)
It may "bypass" the locking of the records it's ready but it does not improve performance or reduce any overhead one bit.
LOL. That's self-contradictory -- if NOLOCK avoids locking that the statement would otherwise have to do, it de facto improves performance.
I'm not saying NOLOCK should be used indiscriminately. I'm saying it does have proper uses because it DOES reduce overhead.
Just because it's often overused and/or misused is no reason to falsify what it does or does not do.
NOLOCK can be useful, for example, for code lookup tables, such as state code lookups. A state hasn't been added since 1959, I think I'll risk it :-).
Also, for example, if/when I'm forced to do read(s) from very busy production table(s) and I want to insure that I don't interfere with production processing.
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