Building Real time Data in Web Applications with Node.js

If you need a NoSQL database which work with JSON data, has full support for realtime searching and has a mix of paradigms between SQL and NoSQL, a good option is RethinkDB.
This is a open-source database, which all JSON’s data is persisted into tables like a conventional SQL database, allowing you to run queries among multiple tables using the classic join command. But you can also persist arrays and sub-documents like you are used to do it in MongoDB, CouchDB or PostgreSQL.