Depends on what the usage of the data would be, and who the client would be and are we talking one client or lots of clients?
A simple file that is memory mapped can be a super easy and fast, simple database. But it gets more nuanced if you say 100 users might use it, then the code required would be substantial to deal with contention, changes etc. Then you are better off just using a real database.
There just isn't enough information to give you a good opinion. If you can answer some of the unknowns like usage, read only read/write single user or multiple and where would it be deployed then it can be a lot easier to give a decent opinion.
A simple file that is memory mapped can be a super easy and fast, simple database. But it gets more nuanced if you say 100 users might use it, then the code required would be substantial to deal with contention, changes etc. Then you are better off just using a real database.
There just isn't enough information to give you a good opinion. If you can answer some of the unknowns like usage, read only read/write single user or multiple and where would it be deployed then it can be a lot easier to give a decent opinion.