The first step in PRD report development is to create a database connection and execute one or more queries. This section explains how to create a MongoDB connection and query. When creating a MongoDB connection, there are several MongoDB-specific configuration options. We do not use some of the more advanced configuration options for exercises in this book, but it is important to be aware of them. MongoDB-specific configuration features, which are not used in the exercises, include the following:
Use all replica set members: Replica sets provide redundancy and increase data availability. If there is a replica set with more than one host, Pentaho discovers all hosts listed in the host field.
Read preference: This tells Pentaho which node to read first—primary, primaryPreferred, secondary, secondaryPreferred, or nearest.
Tag set: Tag sets let you customize write concern and read preferences for a replica set.
Fields expression: This controls the query fields...