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.
Perform the following steps to create a quick sample for users with MongoDB Map/Reduce in PDI:
Let's install the Ivy PDI MongoDB by performing the following steps:
On the menu bar of Spoon, select Help and then Marketplace.
A PDI Marketplace popup will show you the list of plugins available...