Re: statistics target for columns in unique constraint? - Mailing list pgsql-performance

From ach
Subject Re: statistics target for columns in unique constraint?
Date
Msg-id 1368891351220-5756093.post@n5.nabble.com
Whole thread Raw
In response to Re: statistics target for columns in unique constraint?  (Mark Kirkwood <mark.kirkwood@catalyst.net.nz>)
Responses Re: statistics target for columns in unique constraint?
List pgsql-performance
Thanks guys!  I'm gonna try tuning the statistics back down to 10 on that
table and see what that does to the insertion rates.  Oh and for Mark:  Not
to worry - i'd actually tuned the stats there up myself awhile ago in an
experiment to see if -that- would've sped insertions some; back before i'd
had enough mileage on postgres for it to have occurred to me that might just
have been useless ;-)

One quick follow up since I'm expecting y'all might know:  Do the statistics
targets actually speed performance on an index search itself; the actual
lookup?  Or are the JUST to inform the planner towards the best pathway
decision?  In other words if I have statistics set to 1000, say, in one
case, and the planner chose the exact same path it would have if they'd just
been set to 100, would the lookup return faster when the stats were at 1000?
Or would it actually take the same time either way?  My hunch is it's the
latter...




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