Re: LIMIT clause optimization

  Why? I don't understand. If I create a query and want just the first
row from it, wouldn't speed up things a lot just adding "LIMIT 1" in the
end of the query?

On Tue, 2003-01-07 at 10:44, Holger Klawitter wrote:
> Am Dienstag, 7. Januar 2003 12:47 schrieb Felipe Schnack:
> >   I was wondering... (a newbie starting to understand how to optimize
> > queries)
> >   In which step of query execution the LIMIT clause is executed? I mean
> > I have a query that would return, let's say, 6 rows, but I add a "LIMIT
> > 1" in the end of it.
> >   I would speed up things because I would have less data fetching from
> > the database, right?
> 
> Limit kicks in quite late as it has to be done after sorting. And it is not 
> recommended to use LIMIT without ORDER BY.
> 
> With kind regards / mit freundlichem Gruß
> 	Holger Klawitter
> --
> Holger Klawitter                          http://www.klawitter.de
> lists@klawitter.de
-- 

Felipe Schnack
Analista de Sistemas
felipes@ritterdosreis.br
Cel.: (51)91287530
Linux Counter #281893

Centro Universitário Ritter dos Reis
http://www.ritterdosreis.br
ritter@ritterdosreis.br
Fone/Fax.: (51)32303341