populate - Mongoose query a populated field

Question

   db.History.find({'_file.project': 'someproject' )
      .populate('_file', 'name reference project')
      .sort(sortField || '-created')
      .limit(max || 64)
      .exec(this);

Here I'm trying to find all documents which match on a populated field from the _file reference. Is doesn't seem to work. Is something like this possible at all?

I could duplicate the project field to this object, as a workaround just for querying but I'd rather not of course.

Answer 1

No, a find query's conditions parameter can only reference the collection being queried.

populate is not a join, it's just a convenience function to follow up the main query with additional queries to pull in the associated data from other collections.