Named Graph support lands in DiscoverEd
nathan, September 1st, 2010
Earlier this week we updated the master branch on the DiscoverEd project. While this “release” contains many improvements, the biggest one by far is the use of named graphs for tracking provenance. The initial DiscoverEd prototype supported multiple curators making statements about the same resource. For example, the same photograph of the US moon landing might be useful for both a history and a physics course. Unfortunately the initial prototype didn’t retain information about who made each individual statement, which limited the ways in which you could refine your search.
With this week’s release we’re storing that information, and opening up more ways to explore the metadata stored about resources. We use Jena as our RDF store, and Named Graphs for Jena (NG4J) provide an elegant way to integrate this source information with DiscoverEd.
Also notable in this release is database independence. Any database backend supported by NG4J can be used with DiscoverEd, and the default configuration uses Derby for ease of experimentation and development.
Because we did not store metadata previously, we’re recrawling our sources now. Our instance of DiscoverEd will be updated with this code over the next week or two.