Re: Index Scans become Seq Scans after VACUUM ANALYSE

mlw wrote:
> Andrew Sullivan wrote:
> 
> > > Now, given the choice of the two strategies on a table, both pretty
> > > close to one another, the risk of poor performance for using the
> > > index scan is minimal based on the statistics, but the risk of poor
> > > performance for using the sequential scan is quite high on a large
> > > table.
> > 
> > I thought that's what the various cost estimates were there to cover.
> > If this is all you're saying, then the feature is already there.
> 
> The point is that if the index plan is < 20% more costly than the sequential
> scan, it is probably less risky.

I just posted on this topic.  Index scan is more risky, no question
about it.

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