Database

using (OleDbConnection conn = new OleDbConnection(ConnectionString))
{
try
{
conn.Open();
OleDbCommand selectCmd = new OleDbCommand("select * from tableA where col1=? and col2=?", conn);
selectCmd.Parameters.AddWithValue("@col1", val1);
selectCmd.Parameters.AddWithValue("@col2", val2);

OleDbDataAdapter adapter = new OleDbDataAdapter(selectCmd);
OleDbCommandBuilder builder = new OleDbCommandBuilder(adapter);

DataSet selectDS = new DataSet();
adapter.Fill(selectDS, "TableA");

DataTable table = selectDS.Tables["TableA"];
DataRow row = null;
					
int mode = 0;		//0 = create, 1 = edit

if (table.Rows.Count > 0)
{
row = table.Rows[0];
mode = 1;
}
else
{
row = table.NewRow();
}
					
row["col1"] = val1;
row["col2"] = val2;
row["col3"] = val3;

if (mode == 0)
{
table.Rows.Add(row);
}

adapter.Update(selectDS, "TableA");  // this is where the problem occurs
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
finally
{
conn.Close();
}
}