>The cons of course would be that I could corrupt the database, and get
>access to data that the original programmer never intended that I see.
>
>corrupt the database? how so?

huh! Did I just write 'newbie' across my forehead?

Maybe not 'corrupt' the database in an unusable way, but certainly you could
bypass and checks that the programmer had written into the application.
ie test that a TFN is valid (via certain formulaes) before allowing it into
the database.

I guess it could be argued that it is up to the programmer of the original
application to ensure the database is correctly designed. ie a well designed
database should be able to avoid these traps??