Steven the info below was extracted from the following MS web site:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/fox7help/html/dgtskDisplayingStructureOfView.asp

Creating an Index on a View
You can create local indexes on a view, just as on a table, using the INDEX ON command. Unlike indexes you build on a table, local indexes you create on a view are not stored persistently: they vanish when you close the view.

Tip Consider the size of your view's result set when deciding whether to create a local index on a view. Indexing a large result set can take a long time, and slow down performance of your view.
For more information on creating indexes, see Working with Tables, or see INDEX.



>Will the index file be deleted when the user closes the app to keep the folder clean?