[Geoff Bacon]

As Mike said earlier in this thread, there is no current way to import multiple files with a single .csv file - the .csv file only identifies each piece within a multi piece file.

Assuming you can generate a .csv file for a single file, I don't see why you couldn't use that to import the single song along with any metadata that you can generate from your database (I haven't tried it).
While this should do what you want for a single song, I've no idea whether MSP allows you to import multiple .csv files, with associated songs, at the same time.

Suggest you experiment with 3 songs.

Another option, but not so nice might be to merge several of your pdf's into a single file and generate a single .csv for them.
This would reduce the number of .csv files you would have to import if MSP can only handle one at a time.
Ideally, do this for songs that don't change.

Again, experiment to see what works best for you

Sciurius has some tools (https://github.com/sciurius/MSPro-Tools) that can manipulate the database - I've no idea whether these would be useful to you.

Geoff