Re: index or not

Jean-Yves F. Barbier <12ukwn@gmail.com> wrote:

> On Mon, 12 Dec 2011 19:15:32 +0100
> Andreas Kretschmer <akretschmer@spamfence.net> wrote:
>
> > > I wonder if indexes are relevant or not on a small table?
> > > (250 rows, 10 columns, often retrieved in different order)
> >
> > Don't ask us, ask EXPLAIN instead! ;-)
>
> The PB is, it is in dev state and not filled; from what I read
> on the site about indexes, I would say "no" -  so I ask here to
> see if somebody has a return of experience.

As i said: use EXPLAIN. The answer of your question depends on a lot of
details, i can't say if an seq-scan is cheaper or not. (for instance, if
you have SSDs, a index-scan maybe is cheaper than an seq-scan ...)

Create an Index, use explain, if it use a seq-scan you can drop the index.

For such small tables it is hard to guess the plan...


Andreas
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