Aggregation Commands

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Note

For details on specific operator, including syntax and examples, click on the specific operator to go to its reference page.

Aggregation Commands

Name	Description
`aggregate`	Performs aggregation tasks such as group using the aggregation framework.
`count`	Counts the number of documents in a collection or a view.
`distinct`	Displays the distinct values found for a specified key in a collection or a view.
`group`	Deprecated. Groups documents in a collection by the specified key and performs simple aggregation.
`mapReduce`	Performs map-reduce aggregation for large data sets.

Aggregation Methods

Name	Description
`db.collection.aggregate()`	Provides access to the aggregation pipeline.
`db.collection.group()`	Deprecated. Groups documents in a collection by the specified key and performs simple aggregation.
`db.collection.mapReduce()`	Performs map-reduce aggregation for large data sets.