Database Commands From C# Form. It Works But ...

Question

Hello. I am working on a simple C# application to deal with an Access database. This is what I am using for my INSERT/DELETE/UPDATE/SELECT operations: ============== OleDbConnection myConn = new OleDbConnection(myConnString); OleDbDataAdapter da = new OleDbDataAdapter(); DataSet ds = new DataSet(); string mySQLString = "SQL for INSERT/DELETE/UPDATE/SELECT"; try { da.SelectCommand = new OleDbCommand(mySQLString, myConn); da.Fill(ds); // Use ds.Tables[...] if SELECT operation ds.Clear(); ds.Dispose(); da.Dispose(); } catch (System.Exception x) { MessageBox.Show(x.ToString()); } ============== It works, but is it right? Not many, if at all any, of the coding examples I've come across seem to go this way. Here's what's bothering me ... (1) Is it a good idea to not open/close one's connections explicitly? (2) Is it a good idea to have not utilized the ExecuteNonQuery() method? (3) Is there anything that's redundant above? Perhaps the Clear() and Dispose() commands. (4) Would I be paying a heavy price in resources/speed if I were to use Transactions? (5) My updated values (if at all updated values, else old values) for the database are in a textfile. At present I am taking them line by line for INSERT? Is there a faster way? The textfile could have new rows as well, so I: try {INSERT} catch (System.Exception) { try { DELETE; INSERT; } catch (System.Exception x) {MessageBox.Show(x.ToString());} } (6) Is OleDb passe? Should I go SqlClient? Again, it's a simple (4-Table) Access Database. I agree, that's a lots of questions. All and any comments/answers will be helpful. Anything I am missing, anything that could be catastrophic, anything I should look-up. Thanks in advance!