Kelly Jones wrote:
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?
Perhaps use PL/R plus one of the R packages available here: http://cran.stat.ucla.edu/web/packages/ (e.g. http://cran.stat.ucla.edu/web/packages/igraph/index.html) to enable data storage in Postgres and data processing in R. R: http://www.r-project.org/ PL/R: http://www.joeconway.com/plr/ HTH, Joe ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to majordomo@xxxxxxxxxxxxxx so that your message can get through to the mailing list cleanly
