Re: benchmarking the query planner

Alvaro Herrera wrote:
> Tom Lane escribi?:
> 
> > If you want ANALYZE to be cheap then you simply don't get to have a
> > trustworthy value of ndistinct.
> 
> But then, maybe it's not all that critical that ANALYZE is cheap.  For
> example, if we were to rework VACUUM ANALYZE so that on the same pass
> that VACUUM cleans each heap page, a callback is called on the page to
> grab the needed stats.
> 
> Partial vacuum is a roadblock for this though :-(

Perhaps it isn't because partial vacuum is going to highlight the
_changed_ blocks, which fits into your idea of merging stats, somehow. ;-)

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