A patent like this http://www.freepatentsonline.com/y2016/0342709.html is a straightforward way of persisting graph data on RDBMS. If I wish to create an open source alternate implementation of a GraphDB with similar design, should I be bothered? Can I get away with minor tweaks in the design?
If you live in a country with software patents, just take your business elsewhere. If you live in a democracy make sure next time you vote you vote against software patents.
