Re: for/loop performance in plpgsql ?

On Tue, Nov 19, 2002 at 12:23:56AM -0500, Tom Lane wrote:
> > result record;
>
> > for result in select rai, tem
> >                 from data
> >                 where (codice LIKE cod_staz and
> >                 ora > orain and
> >                 ora <= orafin) loop
>
> Which of these names are columns of the selected tables, and which ones
> are plpgsql variables?

rai, tem, codice, ora     are columns name
cod_staz, orain, orafin are plpgsql variables

> The planner has to fall back to default selectivity estimates when it's
> looking at queries involving plpgsql variables (since it can't know
> their actual values in advance).  I suspect your problem is related to
> an inaccurate default estimate.

mmm... does it mean that i can't do anything about that ?