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Date: Tue, 29 Jun 2004 10:28:17 -0400
From: Rich Hall <rhall@micropat.com>
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To: pgsql-sql@postgresql.org
Subject: Re: FW: "=" operator vs. "IS"
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My question is why is the form

"(anything) = NULL"

allowed?

Since

"(anything) = NULL" is always Null, this cannot be what the coder intended. 

This is much different when comparing two variables, where the coder may have to handle the cases where the variables are Null. Here the comparison is to a constant.




Rick