Изменение данных, выведенных в DataGridView

SQLiteConnection conn = new SQLiteConnection("Data Source=voenka.db; Version=3;");
                conn.Open();
                SQLiteCommand sqlCom = new SQLiteCommand("SELECT id_stud,famil,nam,otch,date,pas,prop,departament.NAME,status.NAME,facultet.NAME,course.name,spetial.NAME,start,end,prik,rem FROM student LEFT JOIN facultet,departament,status,spetial,course ON student.fac = facultet.ID_FACULTET AND student.depa = departament.ID_DEPARTAMENT AND student.cours = course.id_course AND student.spetial = spetial.ID_SPETIAL AND student.stat = status.ID_STATUS WHERE ((fac LIKE '" + textBox19.Text + "')  AND (depa LIKE '" + textBox20.Text + "%') AND (spetial LIKE '" + textBox21.Text + "%')  AND (cours LIKE '" + textBox22.Text + "%') AND (date LIKE '" + textBox3.Text + "%') AND (end LIKE '" + textBox5.Text + "%') AND (stat LIKE '" + textBox23.Text + "%'));", conn);
                SQLiteDataReader dr = sqlCom.ExecuteReader();
                SD.DataTable dt = new SD.DataTable();
                dt.Load(dr);
                dataGridView1.DataSource = dt;

SQLiteCommand sqlCom6 = con.CreateCommand();
            sqlCom6.CommandType = CommandType.Text;
            sqlCom6.CommandText = "select id_course,name from course";
            SQLiteDataReader dr6 = sqlCom6.ExecuteReader();
            BindingSource bs6 = new BindingSource();
            bs6.DataSource = dr6;
            comboBox9.DataSource = bs6;
            comboBox9.DisplayMember = "name";
            comboBox9.ValueMember = "id_course";

DataGridView[j, i].Value = ComboBox.Items[i](ну или как там);

SqlCommandBuilder builder = new SqlCommandaBuilder(your adapter);
your_adapter.Update(DataTable);

private void button9_Click(object sender, EventArgs e)
        {
                        //сначало находите номера колонок, которые надо менятся
int columnIndex = 10;
for (int i = 0; i < dataGridView2.Columns.Count; i++)
    if (dataGridView2.Columns[i].HeaderText.Equals(comboBox11.SelectedValue.ToString()))
    {
       columnIndex = i;
       break;
    }
//ну а теперь меняете значение
 
for (int i = 0; i < dataGridView2.Rows.Count; i++)
   dataGridView2[columnIndex , i].Value = comboBox9.SelectedValue.ToString();
            
            SQLiteDataAdapter adapter = new SQLiteDataAdapter();
               SQLiteCommandBuilder builder = new SQLiteCommandBuilder(adapter);
                SD.DataTable dt = new SD.DataTable();
                    adapter.Update(dt);
 
        }

SetConnection();
                con.Open();
                SQLiteCommand sqlCom1 = new SQLiteCommand("SELECT id_stud,famil,nam,otch,date,pas,prop,depa,stat,fac,cours,spetial,start,end,prik,rem FROM student WHERE ((fac LIKE '" + textBox19.Text + "')  AND (depa LIKE '" + textBox20.Text + "%') AND (spetial LIKE '" + textBox21.Text + "%')  AND (cours LIKE '" + textBox22.Text + "%') AND (date LIKE '" + textBox3.Text + "%') AND (end LIKE '" + textBox5.Text + "%') AND (stat LIKE '" + textBox23.Text + "%'));", con);
                SQLiteDataReader dr1 = sqlCom1.ExecuteReader();
                SD.DataTable dt1 = new SD.DataTable();
                dt1.Load(dr1);
                dataGridView2.DataSource = dt1;