We actually did the experiment I mentioned a couple of posts back, about storing RDF triples column-wise. The test loads 4.8 million triples of LUBM data and reads the whole set on one index and then checks if it finds the same row on another index. Reading GSPO and checking OGPS takes 27 seconds.  Doing the same with column wise bitmap indices on S, G, P and O takes 86 seconds.   The latter c ... Continue reading