If these "ghost fields" are a problem, in the sense that you don't even want them to be available as choices in the field list when constructing formulas, there are a couple options:
1. This posting points to a utility on OpenNTF.org that should work:
2. And this posting is to code I personally wrote years ago that should still work for a 6/7 environment (always test though):
This is probably not necessary just to get views working properly, but might if you have LOTS of ghost fields and are actively developing in the database.