Re: COPY and Volatile default expressions

On Mon, Apr 15, 2013 at 05:04:16PM +0100, Simon Riggs wrote:
> On 15 April 2013 16:55, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > Simon Riggs <simon(at)2ndQuadrant(dot)com> writes:
> >> On 15 April 2013 16:24, David Fetter <david(at)fetter(dot)org> wrote:
> >>> Do you have numbers on this, or ways to gather same? In other
> >>> words, how do we know what resources (time, CPU cycles, disk
> >>> seeks, etc.) are being consumed here?
> >
> >> The multi-insert optimisation for COPY is already there and works
> >> well enough to have been committed.
> >
> > You seem to not have answered the question. Exactly what sort of
> > performance gain might be possible, bearing in mind that anything
> > that invokes a trigger (for instance) is unlikely to be amazingly
> > fast anyway?
>
> Forgive me, I assumed the list would be familiar with the
> optimization and so be excited by the need for this.
>
> I will implement as a kluge, test and report the results.
>
> Loading data into a table with a SERIAL or UUID column is the main
> use case, so I'll measure that.

The former is common enough a use case to optimize specifically,
should the numbers come out right. Do you suppose that an in-core
UUID generator would help the latter make more sense as a part of the
same use case?

Cheers,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
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