Re: Short circuit evaluation of expressions in query - Mailing list pgsql-general

From Martijn van Oosterhout
Subject Re: Short circuit evaluation of expressions in query
Date
Msg-id 20060613204054.GH19212@svana.org
Whole thread Raw
In response to Short circuit evaluation of expressions in query  ("Jimmy Choi" <JCHOI@altera.com>)
List pgsql-general
On Tue, Jun 13, 2006 at 02:34:36PM -0400, Jimmy Choi wrote:
> Suppose that at runtime, $1 is supplied a value of -1, does the
> foo.status = $1 condition still have to be evaluated?

SQL doesn't offer any kind of guarentees about order of evaluations,
and neither does postgres. It may occasionally try in an effort to
reduce execution time, but there are no guarentees.

Have a nice day,
--
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> From each according to his ability. To each according to his ability to litigate.

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