bindig Data from A DataBaseccess

OleDbCommand cmd;
                string cmdString = "INSERT INTO  Contacts (FirstName,LastName,Phone,Mobile,Address) values('" + textBoxFirstName.Text + "','" + textBoxLastName.Text + "','" + textBoxPhone.Text + "','" + textBoxMobile.Text + "','" + textBoxAddress.Text + "')";
 
                OleDbConnection myConnection = new OleDbConnection(ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString);
 
                cmd = new OleDbCommand(cmdString, myConnection);
                myConnection.Open();
                cmd.ExecuteNonQuery();
                OleDbCommand myCommand = new OleDbCommand();
                myCommand.CommandText = "Select * from Contacts";
                myCommand.CommandType = CommandType.Text;
                myCommand.Connection = myConnection;
 
                OleDbDataAdapter myAdapter = new OleDbDataAdapter();
                myAdapter.SelectCommand = myCommand;
                myAdapter.Fill(myTable);
                dataGridView.DataSource = null;
                dataGridView.DataSource = myTable.DefaultView;
 
                myAdapter.Dispose();
                myCommand.Dispose();
                myConnection.Close();