What I typically do is:

my $dbh = DBI -> connect ($dsn, $user, $pwd, 
                          {RaiseError => 1, PrintError => 0, AutoCommi
+t => 0})
    or die "Failed to connect: $DBI::errstr\n";

die "Unsetting autocommit failed\n" if $dbh -> {AutoCommit};

eval {
    my $sth = $dbh -> prepare ($sql);
    $result = $sth -> execute (@bind);
}
if ($@) {
    $dbh -> rollback;
    die "Database action failed: $@\n";
}
else {
    $dbh -> commit;
}
[download]

This is for a simple transaction, but if you need to do more actions inside a transaction, you would do all of them inside the eval. Of course, if you want to continue after a failure, you shouldn't do the die.

Abigail