Am 04.05.2010, 19:20 Uhr, schrieb Laurence Rowe <l...@lrowe.co.uk>: > I suspect that databases such as CouchDB and the others you mention > are not well suited to graph traversal. Efficient traversal must occur > near the data, otherwise you pay the latency cost on each edge > traversed. In ZODB this is achieved through the object cache - you > expect most of the target object's parents to already be present in > the cache when serving a request. In other systems traversal happens > in the database - for an example see > http://highscalability.com/neo4j-graph-database-kicks-buttox.
eek! "In essence, each traversal along a link in a graph is a join, and joins are known to be very expensive." Whilst agreeing enthusiastically with Laurence's assertion that you need to be close to the data for efficient traversal, I'm baffled by the reference to Neo4j which contains such guff. Regarding the original question: BFG is well-suited to using different persistence strategies depending on use-case and preference. "Semi-structured data" is, however, an oxymoron albeit a fashionable one. Charlie -- Charlie Clark Managing Director Clark Consulting & Research German Office Helmholtzstr. 20 Düsseldorf D- 40215 Tel: +49-211-600-3657 Mobile: +49-178-782-6226 _______________________________________________ Repoze-dev mailing list Repoze-dev@lists.repoze.org http://lists.repoze.org/listinfo/repoze-dev
