[Mapserver-dev] Displaying a Layer generated "on the fly"

[Thomas Shaw Obregón]

Hello, I'm now using mapserver4 and I have 3 layers in a map that I can
pefectly visualize, the way I'm doing it is with the php-mapscript. Those
3 layers are in shp format, but I also have to generate a new layer with
some data inserted in a data base. The DB has 3 fields
(latitude,longitude,price).
I read the DB record by record and I'm generating  the layer 4 "on the
Fly", when I finish it,I save it to the hard disk, but when I try to
visualize it doesn't appears in the map, there only appears the first
three layers. How can I do to visualize that 4rth layer in the map?

I'll appreciate a lot if anyone  can help me with this.