Re: Highly Efficient Custom Sorting

> On Fri, Jul 2, 2010 at 12:08 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> I'm guessing from tea leaves, but the impression I got from Eliot's
>> description is that he's using plpgsql functions as sort comparators.
>> It's not surprising that that sucks performance-wise compared to having
>> the equivalent logic in C/C++ functions used as comparators on the
>> client side. plpgsql is no speed demon. Best fix might be to code the
>> comparators as C functions on the server side.

On Fri, 2 Jul 2010, Eliot Gable wrote:
> I guess the real question is, is a generic C sorting function my only real
> alternative?

Sounds to me like you are not really listening. You don't need to code an
entire sorting algorithm in C, as Postgres already has a pretty good one
of those. All you need to do is implement a comparator of some kind.
Inserting C functions into Postgres is pretty easy, especially on the
level of comparators.

Matthew

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