Basic, but clear example with everything you need to get this working:
RavenDB is a document database, and unlike a relational database (like say Microsoft SQL Server) – you can’t do your usual group-by type queries quite as simply. […] For RavenDB instead I need to use a Map-Reduce query. The basics of this are that the first part (the Map) runs over the documents, and finds the matches. The reduce then takes the found matches, and summarises (reduces) the result set.
This blog is called myNoSQL and it is written by me, Alex Popescu, a software architect with a passion for open source and communities.
It records my readings, learnings, and opinions on NoSQL databases, polyglot persistence, and distributed systems -- subjects that I'm passionate about.
The opinions expressed here are my own, and no other party necessarily agrees with them.
If you feel I'm biased, I probably am.