Elasticsearch has_child returning no results - elasticsearch

Question

I'm trying to get all child of a parent document but not getting any result with has_child query,
{
"index": "index_x",
"include_type_name": true,
"body": {
"mappings": {
"agents": {
"properties": {
"id": {
"type": "keyword"
},
"listings": {
"type": "join",
"eager_global_ordinals": true,
"relations": {
"agent": "listing"
}
},
"name": {
"type": "object"
}
}
}
}
}
}
here's my query
{
"query": {
"bool": {
"must": [
{
"term": {
"_id": <id>
}
},
{
"has_child": {
"type": "listing",
"query": {
"match_all": {}
},
"inner_hits": {}
}
}
]
}
}
}
however, when I run this query I'm getting child results just fine
{
"query": {
"bool": {
"must": [
{
"parent_id": {
"type":"listing",
"id": <id>
}
}
]
}
}
}
Same with has_parent query, not getting any results.
I'm using Elasticsearch 7.7

Answer 1

Sounds like you want to use the has_parent query. Here is minimal example of how it can work on ESv7.7:
PUT /so
{
"mappings": {
"properties" : {
"my-join-field" : {
"type" : "join",
"relations": {
"parent": "child"
}
},
"tag" : {
"type" : "keyword"
}
}
}
}
POST /so/_doc/1
{
"my-join-field": "parent",
"tag": "Adult"
}
POST /so/_doc/2?routing=1
{
"my-join-field": {
"name": "child",
"parent": "1"
},
"tag": "Youth"
}
POST /so/_doc/3?routing=1
{
"my-join-field": {
"name": "child",
"parent": "1"
},
"tag": "Youth2"
}
GET /so/_search
{
"query": {
"has_parent": {
"parent_type": "parent",
"query": {
"match": {
"tag": "Adult"
}
}
}
}
}