Updating an Access Database

private void button1_Click(object sender, EventArgs e)
        {
            string connectionString = dbProvider + dbSource;
            string queryString=sql;
            DataSet dataSet = new DataSet();
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
                connection.Open();
                OleDbDataAdapter adapter = new OleDbDataAdapter();
                adapter.SelectCommand = new OleDbCommand(queryString, connection);
                OleDbCommandBuilder builder = new OleDbCommandBuilder(adapter);
                adapter.Fill(dataSet);

                string st = "Dizzy blond";

                dataSet.Tables[0].Rows[1].ItemArray[2] = st;

                // Code to Modify

                adapter.UpdateCommand = builder.GetUpdateCommand();
                adapter.Update(dataSet);
            }