Data modeling in Cassandra

I'm building a data base where some users can put tag in others data. Something like Last.fm. How can I implement a DB in cassandra for this application. The Tag must be associate with the user and the data.

Is there any data modeling pattern for cassandra开发者_高级运维?

The Stack overflow tags is a good example of what I want to do! :)

thanks

See http://maxgrinev.com/2010/07/12/do-you-really-need-sql-to-do-it-all-in-cassandra/ and the other articles at the top of http://wiki.apache.org/cassandra/ArticlesAndPresentations

If you haven't already built this in a conventional database I would suggest that first. Most people don't have the data scale to need something like Cassandra. Otherwise if this is simply a project and you want to try out Cassandra then I suggest this link to get you started:

Cassandra by Example : Twitter