I'll let Andy comment on the TDB2 question, but as for compact read-only
storage, you may wish to experiment with HDT [1][2]. It is not supported by the
Jena project, but some Jena users have used it with success.
ajs6f
[1] www.rdfhdt.org
[2] https://github.com/rdfhdt/hdt-java/tree/master/hdt-j
I have a 40MB NT file that once tdb2.tdbload'ed it produces a 85MB database.
Looking inside the Data-0001 directory I see many .dat and .idn files that are
8MB in size. If I remember correctly this structure is used in anticipation of
future modifications of the dataset, therefore some extra spa
