nested aggregation elasticsearch with access parent field for sub-aggregation - elasticsearch

Question

I have following mappings
PUT prod_nested
{
"mappings": {
"default": {
"properties": {
"pkey": {
"type": "keyword"
},
"original_price": {
"type": "float"
},
"tags": {
"type": "nested",
"properties": {
"category": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 30
}
}
},
"attribute": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 30
}
}
},
"original_price": {
"type": "float"
}
}
}
}
}
}
}
I am trying to do something like following sql aggregation
select tag_attribute,
tag_category,
avg(original_price)
FROM products
GROUP BY tag_category, tag_attribute
I am able to do the group-by part using nested aggregation on tags, but its not able to access the original_price in sub-aggregation. One option might be to duplicate the original_price inside the tags nested document, but I have millions of records to handle. My current aggregation is
GET prod_nested/_search?size=0
{
"aggs": {
"tags": {
"nested": {
"path": "tags"
},
"aggs": {
"categories": {
"terms": {
"field": "tags.category.keyword",
"size": 30
},
"aggs": {
"attributes": {
"terms": {
"field": "tags.attribute.keyword",
"size": 30
},
"aggs": {
"price": {
"avg": {
"field": "original_price"
}
}
}
}
}
}
}
}
}
}
Thanks, in advance.

Answer 1

I was able to get the desired results by using reverse_nested aggregation.
GET prod_nested/_search?size=0
{
"aggs": {
"tags": {
"nested": {
"path": "tags"
},
"aggs": {
"categories": {
"terms": {
"field": "tags.category.keyword",
"size": 10
},
"aggs": {
"attributes": {
"terms": {
"field": "tags.attribute.keyword",
"size": 10
},
"aggs": {
"parent_doc_price": {
"reverse_nested": {},
"aggs": {
"avg_price": {
"avg": {
"field": "original_price"
}
}
}
}
}
}
}
}
}
}
}
}

Answer 2

i think what you want is not possible.
but how about change your mapping?
{
"mappings": {
"default": {
"properties": {
"pkey": {
"type": "keyword"
},
"original_price": {
"type": "float"
},
"tags": {
"type": "nested",
"properties": {
"category_attribute": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 30
}
}
},
"category": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 30
}
}
},
"attribute": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 30
}
}
},
"original_price": {
"type": "float"
}
}
}
}
}
}
}
you can use category_attribute.
and your aggregation will be below.
GET prod_nested/_search?size=0
{
"aggs": {
"tags": {
"nested": {
"path": "tags"
},
"aggs": {
"category_attribute": {
"terms": {
"field": "tags.category_attribute.keyword",
"size": 30
},
"aggs": {
"price": {
"avg": {
"field": "original_price"
}
}
}
}
}
}
}
}