my $dbh = DBI->connect( ... {AutoCommit => 1, ..} ) ...

>> perform some method call here < <

 local $dbh->{AutoCommit} = 0;

eval
  {

    # call to EmitSignal on the parent object
    $this->EmitSignal( $event_id, @extra_args );
    # call to Update on another object call "Thread"
    $thread->Update(); #Serialize thread.

   $dbh->commit();

  };

if ($@) {
    $dbh->rollback();
      die $@;
    }


 local $dbh->{AutoCommit} = 1;

...