Re: btree index and max()

> leonbloy(at)sinectis(dot)com(dot)ar wrote:
> >
> > => explain select max(rid) from facturas;
> > NOTICE: QUERY PLAN:
> >
> > Aggregate (cost=21139.66 rows=342414 width=4)
> > -> Seq Scan on facturas (cost=21139.66 rows=342414 width=4)
> >
> > I understand that the query planner cannot be so clever
> > to grasp that this particular function (max or min)
> > might be evaluated by just travelling the BTREE index.
> > Am I correct?
>
> I believe you are unfortunately correct. :(

That would be a good optimization. Let me add it to the TODO list.
Much better than trying to keep the max stored somewhere.

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