mongo scala aggregation renaming group _od

[Colin Bester]

Presently I am using group pipeline with mongo scala driver

group("$status",
 sum("unread", "$numunread"),
 sum("tickets", 1))
))

which results in output of {_id:statusField, unread: .., tickets: ...}

Is there a way to set name of group id to something else besides _id?

[Wan Bachtiar]

Is there a way to set name of group id to something else besides _id?

Hi Colin,

The _id field is part of $group expression and it’s mandatory.
However, you can append a $project stage into the pipeline to rename the _id field.

See also MongoDB Scala Driver 2.2: Aggregate project()

Regards,
Wan.

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