Mongo: how to find by ObjectId that is stored in a subarray?

问题

I have a collection with records like this:

{
    "_id" : ObjectId("50ae3bdb50b3d6f01400027a"),
    "admins": 
       [ObjectId("50ae3bdb50b3d6f014000279"), ObjectId("50ae3bdb50b3d6f01400027e")]
}

I would like to search by the the 'admin' array.

How can I find all documents included for example ObjectId("50ae3bdb50b3d6f014000279") in the sub-array.

Thank you.

回答1:

You can match against array fields like admins the same as you would a non-array field:

db.coll.find({admins: ObjectId("50ae3bdb50b3d6f014000279")})

来源：https://stackoverflow.com/questions/13515728/mongo-how-to-find-by-objectid-that-is-stored-in-a-subarray