On Friday 17 August 2001 10:05, Fabian Groene wrote:
> Hi,
>
> >The usual solution would be a subselect a la:
> >
> > select gname, item, gdate
> > from groups
> > where gdate in (select max(gdate)
> > from groups
> > group by gname)
> >
> >Alas no subselects yet in MySQL (see:
> > http://www.mysql.com/doc/M/i/Missing_Sub-selects.html )
>
> I tried this subquery with an ODBC database that I queried with SQL
> commands. It does not work properly because there were groups of which two
> or more items were shown. That should be avoided ;-(
That's because 'gdate' is being used as the key in this example (health
warning: simplified example, use at own risk ;-). So any group record with
the same date as the most recent date of another group record will
automatically be selected too. Really every record should have a unique key
to avoid this.
HTH
Ian Barwick
--
Ian Barwick - Developer - [EMAIL PROTECTED]
akademie.de asp GmbH - http://www.akademie.de
"To query tables in a MySQL database is more fun than eating spam"
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