Re: Problem whith query in query
| From: | Ryan Gallagher | Date: | Wed, 20 Nov 2002 17:51:27 +0000 |
| Subject: | Re: Problem whith query in query | ||
| References: | 1 2 3 | Groups: | php.general |
| Request: | Send a blank email to php-general+get-125282@lists.php.net to get a copy of this message | ||
Quoting Ernest E Vogelsinger <ernest@vogelsinger.at>:
> At 18:29 20.11.2002, Ryan Gallagher said:
> --------------------[snip]--------------------
> >SELECT * FROM identifisering as i
> >WHERE i.identifiseringid = (
> > SELECT MAX(ii.identifiseringid) AS maxIdentifiseringid
> > FROM identifisering as ii
> > )
> >GROUP BY dprosjekt
> >
> >Now that I look at it, your GROUP BY was definitely out of place, since
> >dprosjekt no doubt is a col being returned from the SELECT * of the main
> >query.
> --------------------[snip]--------------------
>
> No, it wasn't.
> You need the GROUP BY in the subquery to retrieve the max(id) for any
> distinct dprosjekt. If you have it like you did the subquery would simply
> return a single result, the max(id) of all records. Your version simply
> functions as an "order by" which is useless here since only a single record
> will be returned.
Sorry, that's what I was trying to decipher... The '=' combined with the use of
MAX led me to believe the desired recordset size was ONE in the sub query.
--
Ryan T. Gallagher
ryan@studiesabroad.com
International Studies Abroad
http://www.studiesabroad.com
(512)480-8522