On Sun, Jul 30, 2006 at 11:27:33AM -0400, Tom Lane wrote:
> David Fetter <david@fetter.org> writes:
> > On Sat, Jul 29, 2006 at 09:44:10PM -0400, Tom Lane wrote:
> >> The correct solution is for client-side libraries to provide the
> >> feature.
>
> > Not if the app is written in SQL, as the bootstrap, regression
> > test, etc. code for modules frequently is.
>
> SQL doesn't really have any conditional ability strong enough to
> deal with existence or non-existence of features. What are you
> hoping to do, a CASE expression? Both arms of the CASE still have
> to parse, so I remain unconvinced that there are real world uses.
Failure to parse means the transaction bails out, which is just what I
want in my case, as it disallows people attempting to run the
programs--they're for DBI-Link--on too early a version of PostgreSQL.
As there are some subtleties to the implementation, I need something
that quickly returns boolean or fails entirely when it detects same.
Cheers,
D
--
David Fetter <david@fetter.org> http://fetter.org/
phone: +1 415 235 3778 AIM: dfetter666
Skype: davidfetter
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