Re: Optimize ORDER BY ... LIMIT

Gregory Stark wrote:
> Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> writes:
>
> > I believe a better way to think about this would be as an aggregate that
> > remembers the top N rows.
>
> Wouldn't such a thing just be a reimplementation of a tuplestore though? I
> mean, it's storing tuples you feed it, sorting them, and spitting them back
> out in sorted order.

I don't know if this is the same thing you are talking about, but Oleg
talked to me on the conference about "partial sort", which AFAICS it's
about the same thing you are talking about. I think Teodor submitted a
patch to implement it, which was rejected because of not being general
enough.

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