how to create dynamic document keys in mongodb

Question

My problem consists of creating a collection with dynamic fields and undefined names which should be entered by the user. So I tried doing it using variables but it's not working.

This is the code

insertData_dynamic_colone : function(collection) {        
    var colone1 = "prod";
    var colone2 = "prod2";
    dbObject.collection(collection).insertOne({
        colone1 : "14",
        colone2 : "15"
    }, function(err, result) {
        assert.equal(err, null);         
    });
},

So on the database I am getting

> db.colone_dynamic.find()
{ "_id" : ObjectId("579af3c4f41e03f0362a5170"), "colone1" : "14", "colone2" : "15" }

But I'm expecting to get

> db.colone_dynamic.find()
    { "_id" : ObjectId("579af3c4f41e03f0362a5170"), "prod" : "14", "prod2" : "15" }

if you are using schema less method, then you can directly give any name to field name — chirag, Jul 29 '16 at 07:23

score 1 · Answer 1 · answered Jul 29 '16 at 07:13

1

Try:

insertData_dynamic_colone: function(collection) {
  var data = {
    colone1: "prod",
    colone2: "prod2"
  };
  dbObject.collection(collection).insertOne(data, function(err, result) {
    assert.equal(err, null);
  });
},

answered Jul 29 '16 at 07:13

Arun Ghosh

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chridam · Accepted Answer · 2016-07-29T07:37:08.917

Use the bracket notation to construct the document dynamically. You need to first create an empty object that will hold the keys and then use the bracket notation to add the dynamic fields to the object:

insertData_dynamic_colone: function(collection, colone1, colone2) {
    var obj = {};
    obj[colone1] = "14";
    obj[colone2] = "15";
    dbObject.collection(collection).insertOne(obj, function(err, result) {
        assert.equal(err, null);         
    });
}

or

insertData_dynamic_colone: function(collection) {

    var obj = {},
        colone1 = "prod",
        colone2 = "prod2";
    obj[colone1] = "14"; // bracket notation
    obj[colone2] = "15";

    dbObject.collection(collection).insertOne(obj, function(err, result) {
        assert.equal(err, null);         
    });
}

Or, you can use ES2015 Object initializer syntax (as pointed out by @xmikex83 in comments):

insertData_dynamic_colone: function(collection) {

    var colone1 = "prod";
    var colone2 = "prod2";
    dbObject.collection(collection).insertOne({
        [colone1] : "14", // Computed property names (ES6)
        [colone2] : "15"
    }, function(err, result) {
        assert.equal(err, null);         
    });
}

Or, you can use [ES2015 Object initializer](https://developer.mozilla.org/it/docs/Web/JavaScript/Reference/Operators/Object_initializer) syntax. [This](http://jsfiddle.net/ryansukale/wd4hdee2/) is a simple example. — xmikex83, Jul 29 '16 at 07:29

score 1 · Answer 3 · answered Jul 29 '16 at 07:47

You want to insert document which are formed dynamically.Not really dynamic indexing right. You can use the following to achieve what you want.

insertData_dynamic_colone : function(collection) {
    var colone1 = "prod";
    var colone2 = "prod2";
    var insertObj = {};
    insertObj[colone1] = "14";
    insertObj[colone2] = "15";
    dbObject.collection(collection).insertOne(insertObj, function(err, result) {
        assert.equal(err, null);         
    });
},

how to create dynamic document keys in mongodb

3 Answers3

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