Thanks, that clears it up.

Matt.

_-'-_
  -|-


-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of
Jurjen Oskam
Sent: Wednesday, February 23, 2005 12:23 PM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Re: select query misbehaving?

On Wed, Feb 23, 2005 at 12:02:32PM -0000, Warren, Matthew (Retail)
wrote:

> Ok, I can do that. But, surely NULL != 'VAULT' is not like '%VAULT%' ?

SQL has three valued logic: TRUE, FALSE and UNKNOWN (or NULL):

tsm: SERVER1>select count(*) from volumes

        108

tsm: SERVER1>select count(*) from volumes where pct_reclaim = 0.0

         36

tsm: SERVER1>select count(*) from volumes where pct_reclaim != 0.0

         53

tsm: SERVER1>select count(*) from volumes where pct_reclaim is null

         19

tsm: SERVER1>select count(*) from volumes where pct_reclaim is not null

         90

--
Jurjen Oskam
  "E-mail has just erupted like a weed, and instead of considering
  what to say when they write, people now just let thoughts drool
  out onto the screen." - R. Craig Hogan


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