On my way to the Google Summer of Code Mentor Summit 2009, I accepted DraX’s invitation to give a 1-hour talk about XMMS2 Collections at his work, i.e. Metaweb, in San Francisco.

The topic was somewhat relevant for them as it’s reminiscent of MQL, the query language they developed for Freebase. It’s worth noting that although both share a pool of buzzwords such as “graph”, “loosely-structured”, “querying”, etc., they are not quite the same:

• Freebase is essentially a giant graph-database, which you query with MQL to retrieve graph fragments.
• The XMMS2 database is a flat denormalized store, which you query with graph-structured Collections to retrieve a list of entries.

Note: Collections 2.0 should however allow fancier querying to retrieve tree-shaped structures.

About 10-20 people showed up and listened to me babbling about the concept of Collections, the rationale behind them, the API, Collections 2.0, possible UI uses, what it represents for the user, pointers to S4, etc.

It’s all in those over-engineered slides that I have no choice but to put online, under Creative Commons Attribution-Share Alike 2.5 License, for them to live on forever on the internets. And yes, it’s still either in evil Keynote format (source), or in PDF.

Oh and Metaweb, thanks for the food!