Using fields from parent in child visualisation

[KarolGorecki]

Hi,
I have an index with parent - child join field and I want to create visualisation (e.g. a pie chart) with sum of child field and buckets base on field from parent. My Mapping looks like (this is an example not a real mapping)

 "document": {
  "properties" : {
   "name" : {
      "type" : "text",
      "fields" : {
        "keyword" : {
          "type" : "keyword",
          "ignore_above" : 256
        }
      }
    },
    "document_join_field" : {
      "type" : "join",
      "eager_global_ordinals" : true,
      "relations" : {
        "document" : [
          "child_doc"
        ]
      }
    },
	"sum" : {
	"type" : "long"
	}
  }
}

So my question is - can i somehow use this join field to get to child or parent fields or should just flatten the mapping of my index?

[Stacey_Gammon]

Kibana doesn't have support for this yet (you can follow https://github.com/elastic/kibana/issues/3730). Best route forward is to flatten for first class support in Kibana.