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

Question

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.

Accepted Answer

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

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

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

Solution

Problem