Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Mailing Lists -> Oracle-L -> RE: comparing null values

RE: comparing null values

From: Witold Iwaniec <wiwaniec_at_novalistech.com>
Date: Thu, 30 Jan 2003 12:34:11 -0800
Message-ID: <F001.0053F89A.20030130123411@fatcity.com>


While I agree that it could return the rows, I also understand the system side.
Null is nothing so it can not be compared to anything else, even another null. It is something like:

"I don't know whether it is like '%STU%' or not because it is nothing - I don't know what nothing is"

Witold

-----Original Message-----
Jackson
Sent: 30 January 2003 3:27 PM
To: Multiple recipients of list ORACLE-L

Why is this?? If I know that value X has no value, I certainly know that value X is not like '%STU%' ?????

>From: "Whittle Jerome Contr NCI" <Jerome.Whittle_at_scott.af.mil>
>To: <ORACLE-L_at_fatcity.com>
>CC: <fred_fred_1_at_hotmail.com>
>Subject: RE: comparing null values
>Date: Thu, 30 Jan 2003 13:15:33 -0600
>
>Gary,
>
>Null has no value. It can't be like or not like anything. If you want to
>see the null you'll need to add OR IS NULL to your Where clause.
>
>Jerry Whittle
>ASIFICS DBA
>NCI Information Systems Inc.
>jerome.whittle_at_scott.af.mil
>618-622-4145
>
> > -----Original Message-----
> > From: Gary Jackson [SMTP:fred_fred_1_at_hotmail.com]
> >
> > Can anyone explain why it is that I seem unable to use 'like' and 'not
>like'
> > on columns containing null values. (I am unable to find information
> > regarding this on MetaLink.)
> >
> > For example:
> >
> > SQL> select * from tester2;
> >
> > COL1 COL2 WHATEVER
> > ---- ---- --------
> > 1 1 STUFF
> > 2 2 STUFF
> > 3 3
> > 4 4
> >
> > SQL> select * from tester2 where whatever not like '%STU%';
> > no rows selected
> >
> >
> > My question is why does this not return the 3 & 4 columns?
> >



Protect your PC - get McAfee.com VirusScan Online http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963
--
Please see the official ORACLE-L FAQ: http://www.orafaq.net
--
Author: Gary Jackson
  INET: fred_fred_1_at_hotmail.com

Fat City Network Services    -- 858-538-5051 http://www.fatcity.com
San Diego, California        -- Mailing list and web hosting services
---------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.net
-- 
Author: Witold Iwaniec
  INET: wiwaniec_at_novalistech.com

Fat City Network Services    -- 858-538-5051 http://www.fatcity.com
San Diego, California        -- Mailing list and web hosting services
---------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).
Received on Thu Jan 30 2003 - 14:34:11 CST

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US