Quick Links

Re: FW: "=" operator vs. "IS"

From:	Rich Hall <rhall(at)micropat(dot)com>
To:	pgsql-sql(at)postgresql(dot)org
Subject:	Re: FW: "=" operator vs. "IS"
Date:	2004-06-29 14:28:17
Message-ID:	40E17C81.3090308@micropat.com
Views:	Raw Message \| Whole Thread \| Download mbox \| Resend email
Thread:
Lists:	pgsql-sql

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

In response to

FW: "=" operator vs. "IS" at 2004-06-28 22:17:17 from Dmitri Bichko

Responses

Re: FW: "=" operator vs. "IS" at 2004-06-29 14:47:01 from Michael Kleiser
Re: FW: "=" operator vs. "IS" at 2004-06-29 14:57:45 from Tom Lane
Re: FW: "=" operator vs. "IS" at 2004-06-29 16:27:48 from Peter Eisentraut
Re: FW: "=" operator vs. "IS" at 2004-06-29 17:37:21 from Greg Stark

Browse pgsql-sql by date

	From	Date	Subject
Next Message	Michael Kleiser	2004-06-29 14:47:01	Re: FW: "=" operator vs. "IS"
Previous Message	Phil Endecott	2004-06-29 13:49:31	Re: finding if a foreign key is in use