On Thu, Aug 25, 2005 at 02:29:24PM -0500, Ken Youens-Clark wrote:
> Sorry if this is in the docs somewhere, but is there a recommended way=20
> to use transactions with SPOPS. I can't find anything in the POD, but=20
> it seems I can grab the "global_datasource_handle" and set=20
> "AutoCommit=3D0" and then call "commit" at the end?
I believe there is some documentation somewhere in the docs, but to get you
started, this is what I use in my SPOPS base class with postgres as a datab=
ase
backend. The global $DBH variable holda the Database Handle as returned by =
DBI
and is set by the global_datasource_handle method.
Whenever you need to do things in a transaction, just call start_transactio=
n()
en commit the transaction with commit(), or call rollback if something went
wrong. This also allows some form of nested transactions. Postgress itself
doesn't, so only the outer transaction is a real transaction. Which is usua=
lly
what you want anyway.
=3Dhead2 start_transaction
Start a transaction
=3Dcut
sub start_transaction {
# Disable AutoCommit, start transaction
if ($transactionlevel =3D=3D 0) {
if (!$DBH->{AutoCommit}) {
warn "commiting";
$DBH->commit();
$transactionlevel =3D 0;
}
$DBH->begin_work();
$DBH->do('SET TRANSACTION ISOLATION LEVEL SERIALIZABLE');
$DBH->do('SET CONSTRAINTS ALL DEFERRED');
}
$transactionlevel++;
}
=3Dhead2 commit
Commit your changes to the database
=3Dcut
sub commit {
if ($transactionlevel =3D=3D 1) {
my $rc =3D eval { $DBH->commit };
SPOPS::Exception->throw ($DBH->errstr || 'Commit failed') if (!$rc =
|| $@);
$transactionlevel =3D 0;
} else {
if ($transactionlevel > 0) {
$transactionlevel--;
}
}
}
=3Dhead2 rollback
Rollback any changes you made to the database
=3Dcut
sub rollback {
# Don't do a rollback if we were not in a transaction.
if (!$DBH->{AutoCommit}) {
# Enable AutoCommit, ends transaction support
$DBH->rollback() or
SPOPS::Exception->throw ($DBH->errstr || 'Rollback failed');
$transactionlevel =3D 0;
}
}
--=20
#!perl # Life ain't fair, but root passwords help.
# Eric Veldhuyzen http://terra.nu/
$!=3D$;=3D$_+(++$_);($:,$~,$/,$^,$*,$@)=3D$!=3D~ # eric@ter=
ra.nu
/.(.)...(.)(.)....(.)..(.)..(.)/;`$^$~$/$: $^$*$@$~ $_>&$;` #Perl Monger
|
