Sometimes you need to create a new collection on the fly from a MongoDB aggregation pipeline. Fortunately, you can easily do that with MongoTemplate using the addToSet operation.

Fortunately, MongoDB lets you get the sum of all field values in an aggregation group. And you can handle that with MongoTemplate in Spring Boot.

Sometimes you just need the first element in a group you retrieved with a MongoDB aggregation. Fortunately, that's easy to do with MongoTemplate in Spring Boot.

It's often the case that you'll use a MongoDB aggregation pipeline to group related documents. Fortunately, you can do that easily in Spring Boot with MongoTemplate.