reactivemongo.api.commands.AggregationFramework
the name of the field to aggregate on
the sequence of operators specifying aggregate calculation
the name of the field to aggregate on
(groupField: StringAdd).self
(groupField: StringFormat).self
(groupField: ArrowAssoc[GroupField]).x
(Since version 2.10.0) Use leftOfArrow
instead
(groupField: Ensuring[GroupField]).x
(Since version 2.10.0) Use resultOfEnsuring
instead
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