Issues with an embedded relationship query in MongoDb -


i need performing query on embedded relationship in mondodb.

i have users collection array list of friends each user. array holds document id key users _id object.

what want return list of friends of users friends information such firstname, lastname, , email. in fact schema looks like.

users schema

 _id: objectid(),  firstname: string,  lastname: string,  email: string,  friends: [ { id: objectid()}, { id: objectid }, { id: objectid } ]

i think of query similar this:

db.users.aggregate([   { $lookup: { from: 'users',                localfield: 'friends.id',                foreignfield: '_id',                as: 'my_friends'} },    { match: { email: 'someones_email@yahoo.com' }}   ])

this looks referenced relationship on same collection rather one. possible?


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