me sale este error: la entrada de la consulta debe contener al menos una tabla o consultar mi código es:

    using (OleDbConnection myCon = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=timetabledata.accdb")){                       
        OleDbCommand cmd = new OleDbCommand();
        cmd.CommandType = CommandType.Text;
                           string q = "INSERT INTO timehourly (teacherid,subjectid) Values ('@teacherID','@subjid')" + " WHERE hour='@i' AND dayid='@ds'";
                          cmd.Parameters.AddWithValue("@teacherID", Convert.ToInt32(teacher_combo.SelectedValue).ToString());
                           cmd.Parameters.AddWithValue("@subjid",  Convert.ToInt32(subject_combo.SelectedValue).ToString());
                           cmd.Parameters.AddWithValue("@i",i.ToString());
cmd.Parameters.AddWithValue("@ds",ds.Tables[0].Rows[k].ItemArray[0].ToString());
                            cmd.CommandText = q;
        cmd.Connection = myCon;
        myCon.Open();
        cmd.ExecuteNonQuery();
        System.Windows.Forms.MessageBox.Show("successfully added", "Caption", MessageBoxButtons.OKCancel, MessageBoxIcon.Information);}