> 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
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
