Re: default_stats_target WAS: Simple postgresql.conf wizard

* Josh Berkus <josh(at)agliodbs(dot)com> [081202 15:54]:

> Do you have any idea how skewed the distribution of data for DBT3 is? If
> values are being generated in relatively equal proportion, I'd expect
> increasing DST to have little effect. The databases where higher DST is
> useful is ones with skewed data distribution.
>
> Unfortunately, all the data examples I could point to are proprietary
> customer databases :-(

But no body's asking anybody to point out "skewed" data... I think it's
*unanimous* that on skewed data, a higher stats target is needed for the
skewed columns.

The question is how much of a penalty the (majority of?) users with "normal"
data columns will have to pay in stats/planning overhead to accomidate a
blanket increase in DST for the (few?) skewed columns.

I think Marks started to try and show that overhead/difference with real
numbers.

My (probably unsubstantiated) bias is showing, but nobody else has (yet)
showed otherwise ;-)

a.

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