方法/命令

In addition to the [aggregation framework](aggregation.html) and [map- reduce](glossary.html#term-map-reduce), MongoDB provides the following methods and commands to perform aggregation:

Count

MongoDB offers the following command and methods to provide count functionality:

• [count](count.html)
• [db.collection.count()](db.collection.count.html)
• [cursor.count()](cursor.count.html)

Distinct

MongoDB offers the following command and method to provide the distinct functionality:

• [distinct](distinct.html)
• [db.collection.distinct()](db.collection.distinct.html)

Group

MongoDB offers the following command and method to provide group functionality:

• [group](group-1.html)
• [db.collection.group()](db.collection.group.html)