Groups documents together to calulate aggregates on document collections.
This command aggregates on one field.
http://docs.mongodb.org/manual/reference/aggregation/group/#_S_group
idField
the name of the field to aggregate on
ops
the sequence of operators specifying aggregate calculation
Groups documents together to calulate aggregates on document collections. This command aggregates on one field. http://docs.mongodb.org/manual/reference/aggregation/group/#_S_group
the name of the field to aggregate on
the sequence of operators specifying aggregate calculation