Re: [HACKERS] WITH RECUSIVE patches 0717

Tatsuo Ishii <[email protected]> Mon, 21 Jul 2008 08:19:35 +0900 (JST)

Newsgroups	gmane.comp.db.postgresql.devel.patches,gmane.comp.db.postgresql.devel.general
Message-ID	<[email protected]>

> > Thus I think we should avoid this kind of ORDER BY. Probably we should
> > avoid LIMIT/OFFSET and FOR UPDATE as well.
> 
> What of index-optimized SELECT max(...) ?

Aggregate functions in a recursive term is prohibited by the
standard. For example, 

WITH RECURSIVE x(n) AS (SELECT 1 UNION ALL SELECT max(n) FROM x)
  SELECT * FROM x;

produces an error.
--
Tatsuo Ishii
SRA OSS, Inc. Japan

-- 
Sent via pgsql-patches mailing list ([email protected])
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-patches