132 Personal Content Experience: Managing Digital Life in the Mobile Age Another aspect related to storage is the system that is used behind the scenes. Is a fi le system suffi cient, or would a media database be 3 needed? There are some trade-offs between the choices. 5.2.1.4 A File System or a DBMS? Speaking of legacy and interoperability, a fi le system is a safe option, as next to all computing systems can manage fi les. Opening, editing, and transferring fi les are standard operations that we take for granted. Furthermore, a fi le system does not, at least in theory, require any administration, unlike several database management systems (DBMSs). Obviously, a zero-administration database system is the only viable choice for consumer-based products. One aspect to consider is effi ciency related to searching. Files can be indexed and searched for, as described above. However, databases, relational or object-oriented, are far more effi cient and sophisticated in supporting complex searches, different views to information, and so forth. The same holds for most operations that need to be performed on content, such as backups and synchronization. Such functionality is built into most DBMSs. Another issue is privacy and metadata management. With fi le-based systems, all additional information related to a fi le needs to be included in the fi le itself. The metadata can be stored in a separate fi le, and the content fi le will just contain a reference to it. Such a method is extremely error-prone, since it is all too easy to separate the fi les from each other (see section 5.5 on metadata manifests). This may also include sensitive information that is private in nature. Should a fi le with such information end up in wrong hands, severe damage may follow. A good example is the recent inclusion of unwanted metadata in some 4 public documents. With a DBMS, metadata can be stored in the database, separately from the content itself. When a piece of content needs to be exported as a fi le, a policy can be applied to determine what (if any) metadata should be included in the fi le that is to be exported. Better still, in case the recipient has a similar DBMS in use, the content can be replicated to the recipient’s DBMS with defi ned security and privacy options, such as what metadata is transferred in the process. 3 A database is also implemented as a fi le (or a collection of fi les), since fi les are where the computers store data in the fi rst place. However, accessing a database (from a user’s point of view) and the way it is organized internally is inherently different from a fi le system. 4 http://www.theregister.co.uk/2004/02/02/microsoft_releases_metadata_removal_tool/