Using transactions

hi,

i using c#.net 2005, sql server 2000.

i have few questions ask. firstly, can me telling difference between code below , same code comments removed:

            string localquery = "select bla bla";
            sqldataadapter _sda;
            datatable _dt;
            sqlcommand _cmd;
            bool iserrcatched = false;
            exception exctothrow = new exception();

            using (sqlconnection _cn = newconnection) // newconnection returns static sqlconnection object
            {
                _cn.open();

                _cmd = new sqlcommand(localquery, _cn);

                //sqltransaction mytrans;
                //mytrans = _cn.begintransaction();
                //_cmd.transaction = mytrans;

                _dt = new datatable();

                _sda = new sqldataadapter(_cmd);

                try
                {
                    _sda.fill(_dt);
                    _sda.dispose();
                    //mytrans.commit();
                }
                catch (exception exc)
                {
                    //try { mytrans.rollback(); } catch {}

                    iserrcatched = true;
                    exctothrow = exc;
                }
                finally
                {
                    _cn.close();
                }

                _cmd.dispose();
            }

            _cmd = null;

            if (iserrcatched)
                throw exctothrow;
            return _dt;


my first question: can there performance loss if uncomment lines transaction usage? mean, when start more timeouts.

my problem goes on. when comment lines , run stress tool, getting "column x not belong table y" errors. if lines not commented not getting error, timeout errors frequently. so, second question: there wrong in query or there bad coding practice following? offer better , more robust sample code block?

by way, connection pooling on. , these errors observed under high loads.

thanks everybody.

could run query(select) in query analyser , see result

 

madhu

 

SQL Server  >  .NET Framework inside SQL Server