Updating embedded document property in Mongodb

Question

I have a document that looks like this:

{     "_id": 3,     "Slug": "slug",     "Title": "title",     "Authors": [         {             "Slug": "slug",             "Name": "name"         }     ] } 

I want to update all Authors.Name based on Authors.Slug. I tried this but it didn't work:

.update({"Authors.Slug":"slug"}, {$set: {"Authors.Name":"zzz"}}); 

What am I doing wrong here?

Answer 1

.update(Authors:{$elemMatch:{Slug:"slug"}}, {$set: {'Authors.$.Name':"zzz"}}); 

Answer 2

You can use update with array filters:
https://docs.mongodb.com/manual/reference/operator/update/positional-filtered/#positional-update-arrayfilters

Probably something like this:

yourcollection.update( {}, {     "$set": {         "Authors.$[element].Name": "zzz"     } }, {     "multi": true,     "arrayFilters": [          { "element.Slug": "slug" }     ] } ) 

Ps.: it will not work in Robo3T as explained here: Mongodb 3.6.0-rc3 array filters not working? However, you can try on a mongo shell with version >= 3.6.