MongoDB - how to update object using a field in the object

Question

how to update certain object using its's id in the posts array for example changing the the first object in posts using it's id

{
"_id" : ObjectId("5e3929127b0a7599f0a33b90"),
"posts" : [ 
    {
        "title" : "title",
        "desc" : "body",
        "id" : ObjectId("5e396faeac120790c4561f4b")
    },
      {
        "title" : "title2",
        "desc" : "body2",
        "id" : ObjectId("5e396faeac120790c4561x2t")
    }
],
"name" : "jarvis",
"email" : "jarvis@yahoo.com",
"password" : "123",
"__v" : 0

}

to be something like this

 {
"_id" : ObjectId("5e3929127b0a7599f0a33b90"),
"posts" : [ 
    {
        "title" : "new title",
        "desc" : "new body",
        "id" : ObjectId("5e396faeac120790c4561f4b")
    },
      {
        "title" : "title2",
        "desc" : "body2",
        "id" : ObjectId("5e396faeac120790c4561x2t")
    }
],
"name" : "jarvis",
"email" : "jarvis@yahoo.com",
"password" : "123",
"__v" : 0

}

You question is a duplicate of https://stackoverflow.com/questions/11372065/mongodb-how-do-i-update-a-single-subelement-in-an-array-referenced-by-the-inde — Azzy, Feb 04 '20 at 14:05
Welcome, similar questions have been answered before eg. [link](https://stackoverflow.com/questions/9401668/updating-a-sub-document-in-mongodb). You can also find more about handling nested documents in MongoDB's [documentation](https://docs.mongodb.com/manual/tutorial/query-embedded-documents/). — Penguin74, Feb 04 '20 at 14:05
Di you want to update always the **first** element in `post[]` or the post having `id = ObjectId("5e396faeac120790c4561f4b")` — Wernfried Domscheit, Feb 04 '20 at 14:25

score 1 · Accepted Answer · answered Feb 04 '20 at 14:11

1

Would be this one with arrayFilters

db.col.updateMany(
   {},
   {
      $set: {
         "posts.$[p].title": "new title",
         "posts.$[p].desc": "new body"
      }
   },
   { arrayFilters: [{ "p.id": ObjectId("5e396faeac120790c4561f4b") }] }
)

arrayFilters have been introduced in MongoDB version 3.6

answered Feb 04 '20 at 14:11

Wernfried Domscheit

54,457
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thanks a lot can you tell good resources to improve my mongodb knowledge – Youssef Maher Feb 04 '20 at 17:11
2

@YoussefMaher, open stackoverflow.com and try to answer the questions of other people. Try to find the solution just based on documentation, without google. – Wernfried Domscheit Feb 04 '20 at 17:12

score 0 · Answer 2 · answered Feb 04 '20 at 14:11

0

Do you mean this?

yourModel.updateOne({
    "posts.id": ObjectId("5e396faeac120790c4561f4b")
}, {
    $set: {
        "posts.0.title": "new title",
        "posts.0.desc": "new body"
    }
}).then(console.log).catch(console.log);

answered Feb 04 '20 at 14:11

Hlib Derbenov

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1

How do you know that you always have to update element 0? The post could be at any position in array `posts[]`. – Wernfried Domscheit Feb 04 '20 at 14:16
@WernfriedDomscheit "for example changing the first object in posts using it's id". That's not the universal solution, I agree. To update а specific element we need to use positional operator $. – Hlib Derbenov Feb 04 '20 at 14:21

MongoDB - how to update object using a field in the object

2 Answers2