Thanks Ragnar. That solved the problem. I still would
like some explanation about this voodoo. Most
importantly, how can I estimage a "good" statistics
number?

thanks,

Eugene

--- Dr NoName <[EMAIL PROTECTED]> wrote:

> > the seqscan is cheaper when a large enough
> > proportion
> > (maybe 5%) of rows are retrieved, and indeed the
> > cost
> > is estimated at 39014
> 
> very good explanation. thank you.
> 
> 
> > try to increase statistics for this column:
> > 
> > ALTER TABLE render ALTER COLUMN person_id
> >   SET STATISTICS 1000;
> > ANALYZE render;
> > 
> > 1000 is the maximum value, and probably overkill,
> > but you might start with that. If this helps, you
> > can
> > try to lower values until you find the lowest one
> > that still suits your data. Usually, 200 is
> enough.
> 
> 
> ok, we're getting into voodoo territory. What is
> this
> "statistics"? How can I see what the current value
> is?
> How can I estimate what's a "good" value? Where can
> I
> find more information about this?
> 
> thanks,
> 
> Eugene
> 
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