I think your best bet is an RDF tool like Jena or Sesame. 10^9 is pushing these engines though. There's an HBase-SPARQL lib, but that's gotta be two years away

I think your best bet is an RDF tool like Jena or Sesame. 10^9 is pushing these engines though. There's an HBase-SPARQL lib, but that's gotta be two years away from stable. For real world problems, I tend to write custom code that's Java NIO heavy. Try to pack the data as efficiently as possible, and minimize disk seeks.