Re: prepared statements and DBD::Pg

On Thu, May 07, 2009 at 02:31:08PM +0100, Tim Bunce wrote:
> On Thu, May 07, 2009 at 04:54:06AM +1200, Andrej wrote:
> > 2009/5/7 JP Fletcher <jpfletch(at)ca(dot)afilias(dot)info>:
> > > Hi,
> > >
> > > I see different behavior with DBI/DBD::Pg (1.607/2.11.8, pg 8.1) when the
> > > first command in a prepared statement is 'CREATE TEMP TABLE'.
> > >
> > > For instance, this works:
> > >
> > > my $prepare_sql =<<SQL;
> > > CREATE TEMP TABLE foo( id int, user_id int,);
> > > INSERT INTO foo(1, 1);
> > > INSERT INTO foo(2, 2);
> > > SQL
> > > my $sth = $dbh->prepare($prepare_sql);
> > >
> > > This produces the error
> > > ERROR: cannot insert multiple commands into a prepared statement
> > >
> > Blessed be CPAN and the manuals for DBD
> > http://search.cpan.org/~turnstep/DBD-Pg-2.13.1/Pg.pm#prepare
> >
> > WARNING: DBD::Pg now (as of version 1.40) uses true prepared
> > statements by sending them to the backend to be prepared by the
> > Postgres server. Statements that were legal before may no longer
> > work.
>
> Sure seems like a bug, or at best a misfeature, that DBD::Pg doesn't
> simply fallback to client-side prepare when a server-side prepare
> can't be performed. I believe DBD::mysql does that.

It's a safety feature. :)

Cheers,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter
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