Updating embedded document property in Mongodb

问题:

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?

回答1:

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

回答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.