Validating POST form data

[pavsid]

This may be a really silly question but is it entirely necessary to validate form data which originates from a html select list consisting of say numbers, before using that data in a database?

The main reason behind the question is that i have a list which is generated by my script and so no input is collected directly from the user. However, if it is possible to submit POST data to that script via an external program or web page then i can see that is definitely necessary - as someone could submit unwanted data to it.

So i guess my real question is, can you submit POST data to an external site?

[opifex]

The form will send the data where ever you tell it to in action="", your own site or somebody elses.
As far as validation... it is always wise to make sure that the sender is sending what you want.... especially if you are feeding a database.