A user-friendly C++ API is available for Redland RDF datastore.
Dataquay is also considered useful for applications unrelated to RDF but require efficient metadata management. Although quite similar in concept, the library is smaller and less sophisticated compared to Soprano. However, Dataquay is distributed under a BSD license unlike Soprano, which uses LGPL. The two libraries' code is not in common, and Dataquay was initially designed independently. It is important to note that the primary work is done by Dave Beckett's Redland C libraries, with David Robillard's Trees store and Turtle I/O implementations.
To build and use Dataquay, the Raptor, Rasqal, and Redland libraries must be installed. However, users should be aware that while Dataquay is a new library intended for use in serious applications, it is written by inexperts in RDF. Therefore, it may not yet have been tested in a real-life application, and there are potential major conceptual and implementation obstacles to consider. Nonetheless, it is expected that Dataquay will evolve over time.
Version 0.2: N/A