elasticsearch/docs/reference/data-analysis/aggregations/search-aggregations-bucket-nested-aggregation.md
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---------

Co-authored-by: Liam Thompson <32779855+leemthompo@users.noreply.github.com>
Co-authored-by: Liam Thompson <leemthompo@gmail.com>
Co-authored-by: Martijn Laarman <Mpdreamz@gmail.com>
Co-authored-by: István Zoltán Szabó <szabosteve@gmail.com>
2025-02-27 17:56:14 +01:00

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---
navigation_title: "Nested"
mapped_pages:
- https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-bucket-nested-aggregation.html
---
# Nested aggregation [search-aggregations-bucket-nested-aggregation]
A special single bucket aggregation that enables aggregating nested documents.
For example, lets say we have an index of products, and each product holds the list of resellers - each having its own price for the product. The mapping could look like:
$$$nested-aggregation-example$$$
```console
PUT /products
{
"mappings": {
"properties": {
"resellers": { <1>
"type": "nested",
"properties": {
"reseller": {
"type": "keyword"
},
"price": {
"type": "double"
}
}
}
}
}
}
```
1. `resellers` is an array that holds nested documents.
The following request adds a product with two resellers:
```console
PUT /products/_doc/0?refresh
{
"name": "LED TV", <1>
"resellers": [
{
"reseller": "companyA",
"price": 350
},
{
"reseller": "companyB",
"price": 500
}
]
}
```
1. We are using a dynamic mapping for the `name` attribute.
The following request returns the minimum price a product can be purchased for:
```console
GET /products/_search?size=0
{
"query": {
"match": {
"name": "led tv"
}
},
"aggs": {
"resellers": {
"nested": {
"path": "resellers"
},
"aggs": {
"min_price": {
"min": {
"field": "resellers.price"
}
}
}
}
}
}
```
As you can see above, the nested aggregation requires the `path` of the nested documents within the top level documents. Then one can define any type of aggregation over these nested documents.
Response:
```console-result
{
...
"aggregations": {
"resellers": {
"doc_count": 2,
"min_price": {
"value": 350.0
}
}
}
}
```
You can use a [`filter`](/reference/data-analysis/aggregations/search-aggregations-bucket-filter-aggregation.md) sub-aggregation to return results for a specific reseller.
```console
GET /products/_search?size=0
{
"query": {
"match": {
"name": "led tv"
}
},
"aggs": {
"resellers": {
"nested": {
"path": "resellers"
},
"aggs": {
"filter_reseller": {
"filter": {
"bool": {
"filter": [
{
"term": {
"resellers.reseller": "companyB"
}
}
]
}
},
"aggs": {
"min_price": {
"min": {
"field": "resellers.price"
}
}
}
}
}
}
}
}
```
The search returns:
```console-result
{
...
"aggregations": {
"resellers": {
"doc_count": 2,
"filter_reseller": {
"doc_count": 1,
"min_price": {
"value": 500.0
}
}
}
}
}
```