Comparing Geospatial Implementation in MongoDB, Postgres, and Elastic Using MongoDB with Kafka - Use Cases and Best Practices Sharding in MongoDB 4.2 #what_is_new New Indexing and Aggregation Pipeline Capabilities in MongoDB 4.2 Managing data and operation distribution in MongoDB Upgrading to MongoDB 4.0 from older versions How to upgrade to MongoDB 4.0 - Percona Europe 2018 Elastic 101 tutorial - Percona Europe 2018 MongoDB – Sharded cluster tutorial - Percona Europe 2017 Percona Live 2017 - Sharded cluster tutorial How sitecore depends on mongo db for scalability and performance, and what it can teach you Antonios Giannopoulos Percona 2016 WiredTiger Configuration Variables Introduction to Polyglot Persistence 
