The fourth episode of the NoSQL Database Podcast, titled "Querying with NoSQL," features a discussion with hosts and guests Keshav Murthy and Prasad Varakur about the differences in querying between NoSQL and relational databases. The episode covers topics such as indexing, MapReduce, and Couchbase's N1QL query language, offering insights into how these elements function within the NoSQL framework. Listeners can access the episode on platforms like iTunes and Pocket Casts, or listen directly through a media player provided. The podcast also invites questions via email and directs listeners to additional resources on Couchbase's developer portal for more information on transitioning from relational databases to NoSQL and querying for data.