I want to insert node in a JSON document like this:

{
"fileName": "l",
"user\_id": "test",
"requestId": "1232",
"feedbackType": "cpd\_mah"
}

Running this code:

```
let $old := $doc/filename
return
  xdmp:node-insert-after($old, object-node{"isSaved": ""})

```

but this is throwing an error **XDMP-CHILDUNNAMED**.