Re: SQL construct not supported in informix ?
From: Jean Sagi <jeansagi_at_myrealbox.com>
Date: Tue, 22 Jul 2003 06:25:14 -0500
Message-ID: <bfj7tu$dre$1_at_terabinaries.xmission.com>
>
>
>
> You can achieve the same result by doing: select a, b from
> Table(Multiset(select col1 as a, col2 as b from mytable)) as foo
>
> However, some other databases would try to expand the subquery and
> find more efficient joins to table in the outer query if there are
> any. Informix won't.
>
>
Date: Tue, 22 Jul 2003 06:25:14 -0500
Message-ID: <bfj7tu$dre$1_at_terabinaries.xmission.com>
Intereting...
Does it work in IDS 9.3 too?
I think the same could be achieved by creating a temporary table:
select col1 as a, col2 as b from mytable into temp tx with no log; select a,b from tx;
Questions:
- Wich is better?
- Why I may want to use a FROM like that?
Chucho!
Kristofer Andersson wrote:
> vk02720_at_my-deja.com (vk02720) wrote in message news:<4d814faa.0307170740.3e983552_at_posting.google.com>...
>
>>The following SQL construct does not work in Informix 7.3 >>select a,b from >>(select col1 a, col2 b from mytable) >> >>This works in Oracle. >>Is this part of SQL standard or an Oracle extension ? >> >>TIA
>
>
>
> You can achieve the same result by doing: select a, b from
> Table(Multiset(select col1 as a, col2 as b from mytable)) as foo
>
> However, some other databases would try to expand the subquery and
> find more efficient joins to table in the outer query if there are
> any. Informix won't.
>
>
-- Atte, Jesús Antonio Santos Giraldo jeansagi_at_myrealbox.com jeansagi_at_netscape.net sending to informix-listReceived on Tue Jul 22 2003 - 13:25:14 CEST