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From "Peter Ondruška" <peter.ondru...@gmail.com>
Subject Re: getting first k rows from a query that satisfy some additional condition
Date Mon, 27 Oct 2008 22:07:12 GMT
Well, in that case database engine has to read all relevant rows, then sort
and only after that it can display the first row(s).

On Mon, Oct 27, 2008 at 23:02, Amir Michail <amichail@gmail.com> wrote:

> On Mon, Oct 27, 2008 at 5:59 PM, Peter Ondruška
> <peter.ondruska@gmail.com> wrote:
> > Please, post the query you are running.
> > There are queries where setMaxRows will not be faster, for example if you
> do
> > GROUP BY or ORDER BY.
>
> The order is important, so I'm using order by.
>
> Amir
>
> >
> > On Mon, Oct 27, 2008 at 22:51, Amir Michail <amichail@gmail.com> wrote:
> >>
> >> On Mon, Oct 27, 2008 at 5:45 PM, Daniel Noll <daniel@nuix.com> wrote:
> >> > Amir Michail wrote:
> >> >>
> >> >> Hi,
> >> >>
> >> >> What is a good way for efficiently getting the first k rows from a
> >> >> query that also satisfy some additional condition to be determined
> >> >> using Java code?
> >> >
> >> > setMaxRows(int) is the standard way of doing this in JDBC, it only
> falls
> >> > over if you later want to retrieve rows k..(2k-1).
> >> >
> >> > Daniel
> >> >
> >>
> >> It's slow with setMaxRows.
> >>
> >> Amir
> >>
> >> >
> >> > --
> >> > Daniel Noll                            Forensic and eDiscovery
> Software
> >> > Senior Developer                              The world's most
> advanced
> >> > Nuix                                                email data
> analysis
> >> > http://nuix.com/                                and eDiscovery
> software
> >> >
> >>
> >>
> >>
> >> --
> >> http://chatbotgame.com
> >> http://numbrosia.com
> >> http://twitter.com/amichail
> >
> >
>
>
>
> --
> http://chatbotgame.com
> http://numbrosia.com
> http://twitter.com/amichail
>

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