MongoDB में नेस्टेड डॉक्यूमेंट्स के लिए एग्रीगेशन

MongoDB में एग्रीगेशन के लिए aggregate() का उपयोग करें। पहले कलेक्शन बनाएं:

> db.demo199.insertOne({
    "details1": {
        "details2": {
            "details3": {
                "Name": "Chris",
                "details4": {
                    "details5": { "v1": 10, "v2": 20, "v3": 30 }
                }
            }
        }
    }
}); 
{ "acknowledged": true, "insertedId": ObjectId("5e3c24aa03d395bdc21346e2") }
> db.demo199.insertOne({
    "details1": {
        "details2": {
            "details3": {
                "Name": "Chris",
                "details4": {
                    "details5": { "v1": 30, "v2": 40, "v3": 50 }
                }
            }
        }
    }
}); 
{ "acknowledged": true, "insertedId": ObjectId("5e3c24ab03d395bdc21346e3") }

सभी डॉक्यूमेंट्स देखें:

> db.demo199.find();

आउटपुट:

{ "_id": ObjectId("5e3c24aa03d395bdc21346e2"), "details1": { "details2": { "details3": { "Name": "Chris", "details4": { "details5": { "v1": 10, "v2": 20, "v3": 30 } } } } }
{ "_id": ObjectId("5e3c24ab03d395bdc21346e3"), "details1": { "details2": { "details3": { "Name": "Chris", "details4": { "details5": { "v1": 30, "v2": 40, "v3": 50 } } } } }

नेस्टेड डॉक्यूमेंट्स के लिए एग्रीगेशन क्वेरी:

> var out = [
    { "$unwind": "$details1.details2" },
    { "$group": {
        "_id": "$details1.details2._id",
        "v1": { "$sum": "$details1.details2.details3.details4.details5.v1" },
        "v2": { "$sum": "$details1.details2.details3.details4.details5.v2" },
        "v3": { "$sum": "$details1.details2.details3.details4.details5.v3" }
    }}
]
> result = db.demo199.aggregate(out);

परिणाम:

{ "_id": null, "v1": 40, "v2": 60, "v3": 80 }