Mongoose - Get list of _ids instead of array of objects with _id

Question

I would like to run following query:

Group.find({program: {$in: [...]}}).lean().select(\'_id\')

And then NOT get following bac

Answer 1

Group.find({program: {$in: [...]}})
  .distinct('_id')

db.collection.distinct(field, query)

Finds the distinct values for a specified field across a single collection and returns the results in an array.

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