want to update only value element of specific key on mongodb

Question

I have a dataset like this:

{
    "_id" : ObjectId("5a7bee68996b551034015a15"),
    "sequenceid" : 1,
    "fruit" : [ 
        {
            "name" : "@APPLE",
            "value" : 2
        }, 
        {
            "name" : "@BANANA",
            "value" : 1
        }, 
        {
            "name" : "@ORANGE",
            "value" : 5
        }
}

want to update only Apple value i.e from 2 to 25. Expected result will be:

{
    "_id" : ObjectId("5a7bee68996b551034015a15"),
    "sequenceid" : 1,
    "fruit" : [ 
        {
            "name" : "@APPLE",
            "value" : 25
        }, 
        {
            "name" : "@BANANA",
            "value" : 1
        }, 
        {
            "name" : "@ORANGE",
            "value" : 5
        }
}

I tried the code but this will replace all entry and do only one entry. My code is

db.Collection.update({'sequenceid': 1}, {$set: {'fruit' : {'name': '@APPLE', 'value': parseFloat(25)}}}, function(error, result){
  if(error){
console.log('error');
} else {
 console.log('success');
}
});

It can produce the result:

{
    "_id" : ObjectId("5a7bee68996b551034015a15"),
    "sequenceid" : 1,
    "fruit" : [ 
        {
            "name" : "@APPLE",
            "value" : 25
        }
}//Delete all my rest entry

How I can Do this. I am a newbie on MongoDB

Yes. I updated the question. Please go through it – Ankit Feb 08 '18 at 07:09 — Ankit, Feb 08 '18 at 07:09

score 2 · Accepted Answer · answered Feb 08 '18 at 07:13

This will update only the first occurrence of record.For reference MongoDB - Update objects in a document's array (nested updating)

db.collection.update({ _id: ObjectId("5a7bf5586262dc7b9f3a8422") ,"fruit.name" : "@APPLE"},
   { $set:
      {
       "fruit.$.value" : 25

      }
   })

score 1 · Answer 2 · answered Feb 08 '18 at 07:11

1

If you are writing JavaScript query then you can update like this

 db.collection.find({'sequenceid': 1}).forEach(function(x){
        x.fruit.forEach(function(y){
                if(y.name=="@APPLE")
                {
                    y.value = 25 
                }
            })
        db.collection.update({_id:x._id},x)
    })

answered Feb 08 '18 at 07:11

Murugan Perumal

975
5
15

It generates error i.e "db.collection.find().forEach is not a function" – Ankit Feb 08 '18 at 07:20

score 0 · Answer 3 · answered Feb 08 '18 at 09:00

db.Collection.update({
            _id: ObjectId("5a7bee68996b551034015a15"),
            "fruit": {
                $elemMatch: {
                    "name": "@APPLE"
                }
            }
        }, {
            $set: {
                "fruit.$.value": 25

            }
        })

In above update operation $elemMatch operator is used to search a value in an array and in $set stage positional operator $ is used to update value of specific key belonging to an array element

want to update only value element of specific key on mongodb

3 Answers3