create an array of strings from and existing array keys

Question

I have the following column returned from ARG:

{
"a": {
    "key1": [
        "text1",
        "text2"
            ]
     }
"b": {
    "key2": [
        "text1",
        "text2"
            ]
     }
}

I'm trying to create another column which would contain a list of all the keys. So in the example above, the new column would contain:

["key1, "key2"]

I also see that I don't have all the functionality to run in ARG so I'm not sure if what I'm trying to do is possilbe.

Answer 1

| mv-expand kind=array doc
| summarize make_list(bag_keys(doc[1]))