Most aggregation operations in MongoDB are done by the Aggregation Framework, which provides better performance, but in some cases, it is necessary that it possesses flexibility that isn't present in it and is just possible with Map/Reduce commands.
Ivy Information Systems has contributed a plugin with two MongoDB steps—MongoDB Map/Reduce and MongoDB Lookup—under the AGPL license. These are available on GitHub at https://github.com/ivylabs/ivy-pdi-mongodb-steps.
To get ready for this recipe, you will need to start your ETL development environment Spoon, and make sure that you have the MongoDB server running with the data from the previous chapters.
Perform the following steps to create ...