Re: LIMIT Optimization

Oleg Bartunov wrote:
> On Fri, 25 Jan 2002, Bruce Momjian wrote:
> 
> > > if I'm not mistaken, it's called partial sorting, when you stop
> > > sorting process after getting desired number of rows specified by LIMIT clause.
> > > it's extremely friendly for web applications, because 90% of users
> > > just read the first page of results. We already discussed this feature
> > > sometime during 7.1 dev and even made very crude patch. In our tests we
> > > got performance win of factor 5-6 ( getting first 100 row from 1mln ).
> > > We hope sometime we'll return to this.
> >
> > But we already have cursor's assuming 10% return.  Is allowing that
> > value to be changed using SET an acceptable solution?
> 
> 
> Bruce, web applicationa are stateless, so forget about cursors.
> I wrote about obvious optimization which is valid for very narrow case,
> but which is widely spreaded.

I am confused.  I thought we already did optimization for LIMIT that 
assumed you only wanted a few values.  Is there something we are missing
there?   I thought the disucssion related only to people using cursors
and fetching only some of the data.

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