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Aggregation Interfaces¶
Aggregation Commands¶
Name | Description |
---|---|
aggregate | Performs aggregation tasks such as group using the aggregation framework. |
count | Counts the number of documents in a collection. |
distinct | Displays the distinct values found for a specified key in a collection. |
group | 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() | Groups documents in a collection by the specified key and performs simple aggregation. |
db.collection.mapReduce() | Performs map-reduce aggregation for large data sets. |