[Pdx-pm] DBI/DBD::Pg SELECT ... FOR UPDATE

[Amy K. Farrell]

This is all from memory, and with Oracle besides, but I think you're
on the right track with this snippet. You need to make sure you create
your database handle with Autocommit => 0, and explicitly commit at
the end of the transaction.

Whether you need the explicit commit is something I'm particularly
fuzzy on. That might be automatic when the connection is destroyed. 

 - Amy

On Tue, Jul 17, 2007 at 02:58:29PM -0700, Roderick A. Anderson wrote:
[...]

> How does/ or does DBI handle row level locks that Postgresql (and I 
> think Oracle) provides.  Do they apply to the database handle ($dbh)?
> 
> So if,
> 
> ###
> my $sth = $dbh->prepare(q{SELECT the, info FROM thetable WHERE the = 'R' 
> FOR UPDATE });
> 
> my $uth = $dbh->prepare(q{UPDATE thetable SET the = ? WHERE info = ?}):
> 
> $sth->execute();
> 
> while(( $the, $info ) = $sth->fetchrow_array ) {
>     # lots of stuff to do
> 
>     if ( $test_results ) {
>        $uth->execute( $the, $inf );
> 
>        # Will this UPDATE work
>        # while preventing the next run of the script from getting to the
>        # currently selected data?
> 
>     }
> }
> 
> And if not is it possible?  How?
> 
> 
> Thanks,
> Rod
> -- 
> _______________________________________________
> Pdx-pm-list mailing list
> Pdx-pm-list at pm.org
> http://mail.pm.org/mailman/listinfo/pdx-pm-list

-- 
A.K. Farrell