loop variable at query...

hi,
 
i want to include variable inside query.. is it possible if i do like this?
 
Dim a  = 1
        for a=1 to 12

            Try
                cmd.CommandText = "update it_report set application=1 where month= '"&a&"' "

                cmd.Connection = con

                con.Open()
                cmd.ExecuteNonQuery()

                DataGrid1.DataSource = cmd.ExecuteReader()

   &n ...