Re: [RFC] Minmax indexes

On 25 June 2013 00:51, Bruce Momjian <bruce(at)momjian(dot)us> wrote:

> On Sat, Jun 15, 2013 at 11:39:23AM -0400, Tom Lane wrote:
> > Simon Riggs <simon(at)2ndQuadrant(dot)com> writes:
> > > On 15 June 2013 00:01, Josh Berkus <josh(at)agliodbs(dot)com> wrote:
> > >> If we're going to start adding reloptions for specific table behavior,
> > >> I'd rather think of all of the optimizations we might have for a
> > >> prospective "append-only table" and bundle those, rather than tying it
> > >> to whether a certain index exists or not.
> >
> > > I agree that the FSM behaviour shouldn't be linked to index existence.
> > > IMHO that should be a separate table parameter, WITH (fsm_mode =
> append)
> > > Index only scans would also benefit from that.
> >
> > -1 ... I cannot believe that such a parameter would ever get turned on
> > in production by anyone. If your table has a significant update rate,
> > the resulting table bloat would make such behavior completely
> > infeasible. If you have few enough updates to make such a behavior
> > practical, then you can live with the expensive index updates instead.
>
> Can you have pages that are receiving updates _not_ track min/max, until
> the page is nearly full? This would require full scans of such pages,
> but there might be few of them. The amount of free spaces on the page
> as reported by FSM might be useful here.
>

Yes, that is the proposal. Just like index only scans.

--
Simon Riggs http://www.2ndQuadrant.com/
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