Let's say I want to use the model outlined in the "File Storage" example. I set up and populate my permission DB accordingly with file permissions, organization and group assignments, etc. I also have an index filled with metadata related to the files that users have uploaded to my service and not just one, but two 500 GB laptop hard drives dedicated to file storage.
User "A" comes along and searches for files matching "ragtime". I can ask the permission DB to return the ID of 1499 files "A" has (directly or indirectly) access to, and also run a free-text search to return cca. 195700 files with a title, description or indexed content that matches "ragtime". But what happens next? Can I return an accurate search hit count or filtered result set to the user from his limited access-point of view? Do I need to move metadata into the permission database to do so?