I have some files in a flat library, i.e., no subfolders, that need to have access restricted to a couple usergroups.
I understand that one way to do this is by placing items in a subfolder in the library and applying the restricted permissions to the subfolder, but I have misgivings about this method...
Namely, there are almost certainly going to be files that need to be accessed by more than one usergroup, and permitting multiple usergroups access would mean there'd be impermissible crossover in file access. Otherwise, I'd need to create and maintain two "versions" of a file, which is generally unacceptable in my design, and I know is generally strongly discouraged. Also, if you need to "folderize" files after they've already been published, the URL changes; also unacceptable.
I'm looking for alternatives.
I've had a fuzzy picture in my head of a lookup column that lists the groups at my site's level, and provides a checkbox to select which usergroups are permitted to access the file, but I don't think such a column exists OOTB, and I wouldn't have a clue where to begin in creating one.
I'm working on SharePoint 2010 Foundation.