Re: Query Help

From: Doug Miller <spambait_at_milmac.com>
Date: Thu, 17 Jan 2008 13:05:45 GMT
Message-ID: <smIjj.261$nK5.202@nlpi069.nbdc.sbc.com>


In article <1c892130-538b-49bd-a6dc-b098222ee311_at_x69g2000hsx.googlegroups.com>, Charles Hooper <hooperc2000_at_yahoo.com> wrote:

>Just a minor correction to my previous post... additional thoughts
>shortly after submitting the previous post. These two logic checks
>are not necessarily equivalent when dealing with data stored in a
>database, but are equivalent when dealing only with Boolean logic:
>IF (AGE <> 65) OR (AGE = 65 AND RETIRED = "Y") THEN
>
>IF (AGE <> 65) OR (RETIRED = "Y") THEN
>
>The first expression does not permit NULL values for the AGE, while
>the second does.

I disagree: if AGE is NULL, then the first clause (AGE <> 65) is true, and in either form, the second clause won't even be evaluated (due to the conjunction).

-- 
Regards,
        Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.
Received on Thu Jan 17 2008 - 07:05:45 CST

Original text of this message