On Wednesday, June 13, 2012 05:03:38 PM Robert Haas wrote:
> On Wed, Jun 13, 2012 at 10:35 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> >> On Tue, Jun 12, 2012 at 9:52 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> >>> The code for this is as attached. Note that I'd rip out the
> >>> normal-path tracking of line boundaries; it seems better to have a
> >>> second scan of the data in the error case and save the cycles in
> >>> non-error cases.
> >>
> >> Really?!
> >
> > Um ... do you have a problem with that idea, and if so what? It would
> > be considerably more complicated to do it without a second pass.
>
> Could you explain how it's broken now, and why it will be hard to fix?
> People may well want to use a cast to JSON within an exception block
> as a way of testing whether strings are valid JSON. We should not
> assume that the cost of an exception is totally irrelevant, because
> this might be iterated.
Exception blocks/subtransctions already are considerably expensive. I have a
hard time believing this additional cost would be measureable.
Andres
--
Andres Freund http://www.2ndQuadrant.com/
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