Re: [GENERAL] why sequential scan is used on indexed column ???

Michael Fuhr <mike@fuhr.org> schrieb:

> On Sat, Jun 14, 2008 at 04:59:44PM +0200, Andreas Kretschmer wrote:
> > Julius Tuskenis <julius.tuskenis@gmail.com> schrieb:
> > > I have a question concerning performance. One of my queries take a long
> > > to execute. I tried to do "explain analyse" and I see that the
> > > sequential scan is being used, although I have indexes set on columns
> > > that are used in joins. The question is - WHY, and how to change that
> > > behavior???
> >
> > Try to create an index on apsilankymai.sas_id
>
> In the DDL that Julius posted apsilankymai doesn't have an sas_id
> column.
>
> The join is on apsilankymai.aps_saskaita = b_saskaita.sas_id. Both
> columns have an index: b_saskaita.sas_id is a primary key so it
> should have an index implicitly, and apsilankymai.aps_saskaita has

Right, my mistake.

Andreas
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