Re: WHERE 1=2 with performance nightmares

Kim Madsen wrote:

Usually the expression compiler will evaluate the expression to be
false, even before actually searching records.

On further thought, doing might violate the SQL standard, which
requires that an error be returned consistently, regardless of
optimization. Hence, if a selectable procedure was going to return an
error without the optimization, it must return the same error with the
optimization, and, practically speaking, the only way to do that would
be to run the query to completion.

--
Craig Stuntz [TeamB] · Vertex Systems Corp. · Columbus, OH
Delphi/InterBase Weblog : http://blogs.teamb.com/craigstuntz
How to ask questions the smart way:
http://www.catb.org/~esr/faqs/smart-questions.html
.

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