LEADING OPEN SOURCE GRAPH DATABASES
Neo4j is a graph database. It is an embedded, disk-based, fully transactional Java persistence engine that stores data structured in graphs rather than in tables. A graph (mathematical lingo for a network) is a flexible data structure that allows a more agile and rapid style of development.
FlockDB is a distributed graph database for storing adjancency lists, with goals of supporting:
– a high rate of add/update/remove operations
– potientially complex set arithmetic queries
– paging through query result sets containing millions of entries
– ability to “archive” and later restore archived edges
– horizontal scaling including replication
– online data migration
Non-goals include:
- multi-hop queries (or graph-walking queries)
- automatic shard migrations
OTHER OOPEN SOURCE GRAPH DATABASES
InfoGrid is an Internet Graph Database with a many additional software components that make the development of REST-ful web applications on a graph foundation easy.
AllegroGraph is a modern, high-performance, persistent graph database. AllegroGraph uses efficient memory utilization in combination with disk-based storage, enabling it to scale to billions of quads while maintaining superior performance. AllegroGraph supports SPARQL, RDFS++, and Prolog reasoning from numerous client applications.