The BeOS "database" is a set of programming interfaces which take advantage of some of the extended features of the Be File System; there is no separate database per se. Instead, what we have is an attribute adorned file system with a query engine for the attributes.
It is not intended to be an Oracle/Sybase/Postgres clone. What we're doing is not a fully relational SQL queriable object oriented super whiz bang database. What we are doing is a method of adding and indexing additional information about entities in a file system name space.