Re: Use of index in 7.0 vs 6.5

> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > That certainly would make sense.  We have hesitated to gather more
> > statistics because of the time involved.  Fuller statistics on just the
> > indexed columns could be a big win and be done fairly quickly because
> > the rows are already sorted in the index.
> 
> Yeah, a scan over just the index itself would be a perfect way to
> gather stats.  The normal objection to it (can't tell whether entries
> correspond to currently-valid tuples) doesn't apply, because we don't
> really care whether the stats are perfectly accurate.
> 
> Should put this in TODO, along with something about splitting the
> ANALYZE function out of VACUUM and making it invokable as a separate
> statement.

Added:

* Remove ANALYZE from VACUUM so it can be run separately without locks
* Gather more accurate statistics using indexes


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