we don't have access to a relational database for this project

If you can install Perl modules than you can install SQLite. It comes bundled with DBD::SQLite. It is a simple C library, and the DB is a single file. Which means no daemon running, no port to open, no admin to do (access rights are the access rights to the file). From an admin point of view it is just like a flat file. Using it is (or at least should ;--) really be a low-level implementation decision.