Return just an object within array from database

Question

I have a db like this

{
    "name": "Tom",
    "cars": [
        {
            "name": "Shirley",
            "kind": "Bugatti"
        },
        {
            "name": "Jessica",
            "kind": "Maserati"
        },      
    ]
}

I have a query like this

db.people.findOne({"name: "Tom"});

I just want to return the object where "name": "Jessica"

{
    "name": "Jessica",
    "kind": "Maserati"
}

How can I do this?

I tried

db.people.findOne({"name": "Tom"}, {"cars.name": 1});
db.people.findOne({"name": "Tom"}, {"cars.name.Jessica": 1});

I'm trying to prevent returning the whole thing then sorting everything after.

Which object are you trying to get to? The second one? The last one? First one alphabetically by name? The "Jessica" object meets several criteria and you didn't spell out what criteria you are searching for. — Brandon, Oct 20 '13 at 21:50
The first object in the query is your filter and the second object is the list of fields to return. You are mixing them. — Brandon, Oct 20 '13 at 21:52
No I'm not. they query is adequate. I'm trying to trim down the fields so that I just return that one object. Attaching a more specific query is still going to give me the whole doc. — ThomasReggi, Oct 20 '13 at 21:55

score 1 · Accepted Answer · answered Oct 20 '13 at 22:18

1

db.people.findOne({"name": "Tom"}, {"cars": { $elemMatch : { "name": "Jessica"}}});

{
    "_id" : ObjectId("526453188257d12214ea287d"),
    "cars" : [
        {
            "name" : "Jessica",
            "kind" : "Maserati"
        }
    ]
}

answered Oct 20 '13 at 22:18

ThomasReggi

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thought you just wanted to project `name:'jessica'`? – sambomartin Oct 20 '13 at 22:19
Why would I want what I queried for? I said what I wanted to return in the question. Sorry for the confusion. – ThomasReggi Oct 20 '13 at 22:22
This is as good as you'll get without using the aggregation framework. – Samuel O'Malley Oct 21 '13 at 00:52

Return just an object within array from database

1 Answers1