CODEWITHSUNDEEP
javascriptnode.jsmongodb
John Lim
John Lim

Reputation: 3109

how to upsert new field in a nested array

hey guys may i know is it possible to upsert new field in a nested array ?

for example a nested array like this.

"comments" : [
        {
            "name" : "john",
            "title" : "Facebook",
            "content" : "LOLOLOLOL",
            "votes" : {
                "up" : [ ],
                "down" : [ ]
            },
            "date" : ISODate("2014-04-24T17:39:49.782Z"),
        }
    ],

is it possible to update this nested array with new field called "scores" ? something like this. 

 "comments" : [
            {
                "name" : "john",
                "title" : "Facebook",
                "content" : "LOLOLOLOL",
                "votes" : {
                    "up" : [ ],
                    "down" : [ ]
                },
                "date" : ISODate("2014-04-24T17:39:49.782Z"),
                "scores": 50
            }
        ],

i have tried this method but i can't seem to make it works 

       // get up vote, down vote to calculate 
    posts.findOne({'comments': { $elemMatch: { permalink: data.permalink } } },function(err, data){
            var ups = data.votes.up.length;
            var downs = data.votes.down.length;
            var marks = favourite(ups,downs);
            var scores = {
                "comments.$.scores":marks
            }
        // insert the scores in a nested array as new field.
    posts.update({'comments': { $elemMatch: { permalink: data.permalink } } },{$set:scores},{upsert:true}, function(err, post) {
            "use strict";
            if (err) console.log(err)
        });
       });

Upvotes: 1

Views: 843

Answers (1)

Andrei Beziazychnyi
Andrei Beziazychnyi

Reputation: 2917

db.yourCollection.update({comments:  {$elemMatch:{ name:"john"} } }},{$set:{"comments.$.scores":50}},{multi:true});

However, only first matched element in nested array for each document would be modified

Upvotes: 1

Related Questions