First take a label. set its visibility to false, then on the DataGridView_CellClick event write this
private void dataGridView1_CellClick(object sender, DataGridViewCellEventArgs e)
{
label.Text=dataGridView1.Rows[e.RowIndex].Cells["Your Coloumn name"].Value.ToString();
// then perform your select statement according to that label.
}
//try it it might work for you