I have a directed graph (nodes and edges) that I want to store "efficiently": given two nodes, I want to quickly find the shortest path between them. The graph is NOT acyclic (it's not a tree), is fairly "sparse" (about 10000 edges for 2500 nodes), and changes occasionally. I know PostgreSQL/MySQL can store graphs (as one table of nodes and one table of edges that reference the nodes), but I think finding the shortest path between two nodes is quite inefficient that way. I know PostgreSQL/MySQL have special "plugins" (like PostGIS for PostgreSQL) for specific problems. Is there a directed graph plugin? I'm not married to using SQL: are there other efficient solutions to store directed graphs? Could I hack something up in Perl or Ruby and then serialize my in-memory graph to a file (for efficient saving/reloading)? As a minor note, the nodes/edges will have (non-unique) names and descriptions, and I want the ability to do fulltext searching on these names/descriptions. However, this is less important than quickly finding the shortest path between two nodes. -- We're just a Bunch Of Regular Guys, a collective group that's trying to understand and assimilate technology. We feel that resistance to new ideas and technology is unwise and ultimately futile. ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq