Re: How to improve this query?

From: Daniel Morgan <damorgan_at_x.washington.edu>
Date: Mon, 24 Nov 2003 06:54:42 -0800
Message-ID: <1069685709.573129@yasure>

Tom Miskiewicz wrote:
> Hi!
>
> Thanks for your reply.
>
>

>>If all you want to test for is not null and your column is indexed then

>
> you
>

>>should use
>>select count(*)
>>from table
>>where col is not null;

>
>
> I have been told, that there is no difference between count(*) and count(1).
> Is that right?
>
> Thomas

or
SELECT Count('I like the color blue')
FROM table;

BTW ... try this test:

SELECT COUNT(*)
FROM all_tables
WHERE NULL = NULL; followed by

SELECT COUNT(*)
FROM all_tables
WHERE NULL <> NULL;

That should prove the point Sybrand and Chris made.

-- 
Daniel Morgan
http://www.outreach.washington.edu/ext/certificates/oad/oad_crs.asp
http://www.outreach.washington.edu/ext/certificates/aoa/aoa_crs.asp
damorgan_at_x.washington.edu
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Received on Mon Nov 24 2003 - 08:54:42 CST