title: OleDbCommand.ExecuteNonQuery() does not save changes in ms access database
body: <p>I have <code>.mdb</code> database, and code like this:</p>
  
  <pre><code>using (OleDbConnection connection = new OleDbConnection(myConnectionString))
  {
      using (OleDbCommand cmd = connection.CreateCommand())
      {
          cmd.CommandText = "UPDATE myTab SET col2 = @val1 WHERE col1 = @val2";
          cmd.Parameters.AddWithValue("@val1", 0);
          cmd.Parameters.AddWithValue("@val2", -1);
          cmd.Connection.Open();
          cmd.ExecuteNonQuery();
          cmd.Connection.Close();
       }
  }
  </code></pre>
  
  <p>I get data from db, change it in my gui programm, then save it in db. Changes saves, but not  in db (I don't know where), so when I run program, change data, close program, then again run - changes remain, but when I open db (not in programm), there are no changes saved, and again run - all changes disappear.<br>
  PS: when I commit changes, then run program several times, all changes disappear too, after (3-4 runs)</p>