error using where clause

Question

guys its really urgent ,


i have a table with two fields s_no and level

both are integers

and i m searching s_no by passing value  for level


but getting the error of datatype mismatch

 int sno = Convert.ToInt32(TextBox1.Text);

            con.Open();

            OleDbCommand cmd = new OleDbCommand("select level1 from memreg where s_no ='"+ sno + "'"  , con);

            OleDbDataReader dr = cmd.ExecuteReader();

            while (dr.Read())

            {

                Label1.Text = dr[0].ToString();

            }