Skip site navigation (1) Skip section navigation (2)

Re: "=" operator vs. "IS"

From: Michael A Nachbaur <mike(at)nachbaur(dot)com>
To: Stefan Weiss <spaceman(at)foo(dot)at>
Cc: pgsql-sql(at)postgresql(dot)org
Subject: Re: "=" operator vs. "IS"
Date: 2004-06-28 22:28:08
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-sql
On June 28, 2004 03:02 pm, Stefan Weiss wrote:
> I'm just curious - why is it not possible to use the "=" operator to
> compare values with NULL? I suspect that the SQL standard specified
> it that way, but I can't see any ambiguity in an expression like "AND
> = NULL". Is it because NULL does not "equal" any value, and the
> expression should be read as " is unknown"? Or is there something
> else I'm missing?

As far as I have been able to tell, it is one of those quirks about SQL that 
you shouldn't bother trying to understand.  It just IS.  <rimshot/>

Michael A. Nachbaur <mike(at)nachbaur(dot)com>

In response to


pgsql-sql by date

Next:From: terryDate: 2004-06-28 23:00:13
Subject: Re: "=" operator vs. "IS"
Previous:From: Steve CrawfordDate: 2004-06-28 22:27:14
Subject: Re: "=" operator vs. "IS"

Privacy Policy | About PostgreSQL
Copyright © 1996-2017 The PostgreSQL Global Development Group