mongoDB: Update nested array object

Question

I would like the nested object with the id BAHx9KeKjuMePce6f to be updated:

{
 "_id" : "sgG6G9XTvvjj7uxwQ",
 "target" : [
 {
 "title" : "content",
 "id" : "ePce6fBAHx9KeKjuM"
 },
 {
 "title" : "content",
 "id" : "BAHx9KeKjuMePce6f" <--
 }
 ]
}

So this is what I tried:

var newData = { title: "new", one: "more", id: 'BAHx9KeKjuMePce6f' };
Collection.update(
 { _id: 'sgG6G9XTvvjj7uxwQ', 'target.id': 'BAHx9KeKjuMePce6f' }, 
 { $set: newData }
);

The result should be:

{
 "_id" : "sgG6G9XTvvjj7uxwQ",
 "target" : [
 {
 "title" : "content",
 "id" : "ePce6fBAHx9KeKjuM"
 },
 {
 "title": "new", 
 "one": "more",
 "id" : "BAHx9KeKjuMePce6f"
 }
 ]
}

Answer 1

In order to update specific element in array you can use mongodb positional $ operator.

Try the following query:

var newData = { title: "new", one: "more", id: 'BAHx9KeKjuMePce6f' };
Collection.update(
 { _id: 'sgG6G9XTvvjj7uxwQ', 'target.id': 'BAHx9KeKjuMePce6f' }, 
 { $set: { 'target.$': newData } }
);

Answer 2

You need the use the positional parameter $ to indicate you want to update the array element, rather than the root of the document, see the documentation:

Collection.update({
 _id: 'sgG6G9XTvvjj7uxwQ',
 'target.id': 'BAHx9KeKjuMePce6f'
}, {
 $set: {
 "target.$": newData
 }
});