Yup. Got it. Wasn't thinking clearly about what expression meant.
Thanks!
-tfo
--
Thomas F. O'Connell
Co-Founder, Information Architect
Sitening, LLC
http://www.sitening.com/
110 30th Avenue North, Suite 6
Nashville, TN 37203-6320
615-260-0005
On Feb 23, 2005, at 2:33 PM, Bruno Wolff III wrote:
On Wed, Feb 23, 2005 at 13:54:50 -0600,
"Thomas F.O'Connell" <[EMAIL PROTECTED]> wrote:
How would one know from the reference material that it is possible to
include IS NOT NULL in an ORDER BY clause?
Similarly, other than the FAQ, I've never been able to tell from the
SELECT documentation why ORDER BY random() works.
From the SELECT command documentation:
SELECT [ ALL | DISTINCT [ ON ( expression [, ...] ) ] ]
* | expression [ AS output_name ] [, ...]
[ FROM from_item [, ...] ]
[ WHERE condition ]
[ GROUP BY expression [, ...] ]
[ HAVING condition [, ...] ]
[ { UNION | INTERSECT | EXCEPT } [ ALL ] select ]
[ ORDER BY expression [ ASC | DESC | USING operator ] [, ...] ]
[ LIMIT { count | ALL } ]
[ OFFSET start ]
[ FOR UPDATE [ OF table_name [, ...] ] ]
Notice that for ORDER BY you can supply an expression. That should be
a big
clue why you can use IS NOT NULL and random() in an ORDER BY clause.
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