[otrs] Reason for Field filename in FAQ->createArticle

Hello, I want to use the faqs in my otrs installation... Can anyone tell me what's the reason for the field "filename" in FAQ? Why is the "filename" the primary Key in the mySQL-Table? I thought faq-articles where supposed to be stored in the database and not in the filesystem. Is it a problem for future releases when I make the filename-field in mySQL an auto_increment field? Another question: Is is possible to use attachments in faq-articles? thanks in advance! Volker