Perl DBI begin_work and nested transactions interacting with SQL Server 2008

I have a script as shown below. In cases where the main method requires calling several methods, 1 method for 1 table, and each method launches a set of operators that must be atomic. Thus, they are enclosed in a begin_work, commit, rollback block.

Also call_method_for_table1, call_method_for_table2, call_method_for_table3 should all succeed or crash together, which means that they must be atomic. That is why the begin_work, commit, rollback block is added in the main method. But I see that perl does not allow me. I get an exception - "DBD :: ODBC :: db begin_work failed: already in the transaction . Now I have no way to change the call_method_for_table * methods, since it is in the library and it cannot be changed for many reasons.

Can I use breakpoints to solve this problem

• Does Savepoints help ( http://msdn.microsoft.com/en-us/library/ms378414%28v=SQL.105%29.aspx )
• Roll back to save the savepoint, even if there are some commits between them (which usually happens in my example)
• Is this good, even if there are parallel runs of the same process?
• Will this cause data inconsistency?

sub main {
        $dbh->begin_work;
           eval {
              call_method_for_table1();
              call_method_for_table2();
              call_method_for_table3();
              $dbh->commit;
              1; 
        };

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

    sub call_method_for_table1 {
    $dbh->begin_work;
           eval {
           $dbh->do($INSERTSTATEMENT_TABLE1);
           $dbh->do($UPDATESTATEMENT_TABLE1);
           $dbh->do($DELETESTATEMENT_TABLE1);
           $dbh->commit; 
           };

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