[Cieplak]

Thanks! I was just reading the neo4j source and noticed the bitmap indexes which apparently have several advantages to B-tree indexes for indexing graphs:

https://github.com/neo4j/neo4j/tree/3.0/community/lucene-ind...

ps:

http://stackoverflow.com/questions/9541541/b-tree-vs-bitmap-...

https://en.wikipedia.org/wiki/Bitmap_index

Thanks for showing me triplestores! Good to know that it's better to use a database engine optimized for triples for graphs vs rolling your own in SQL.