83 lines
2.3 KiB
Plaintext
83 lines
2.3 KiB
Plaintext
[[search-aggregations-reducer-max-bucket-aggregation]]
|
|
=== Max Bucket Aggregation
|
|
|
|
A sibling reducer aggregation which identifies the bucket(s) with the maximum value of a specified metric in a sibing aggregation
|
|
and outputs both the value and the key(s) of the bucket(s). The specified metric must be numeric and the sibling aggregation must
|
|
be a multi-bucket aggregation.
|
|
|
|
The following snippet calculates the maximum of the total monthly `sales`:
|
|
|
|
[source,js]
|
|
--------------------------------------------------
|
|
{
|
|
"aggs" : {
|
|
"sales_per_month" : {
|
|
"date_histogram" : {
|
|
"field" : "date",
|
|
"interval" : "month"
|
|
},
|
|
"aggs": {
|
|
"sales": {
|
|
"sum": {
|
|
"field": "price"
|
|
}
|
|
}
|
|
}
|
|
},
|
|
"max_monthly_sales": {
|
|
"max_bucket": {
|
|
"buckets_paths": "sales_per_month>sales" <1>
|
|
}
|
|
}
|
|
}
|
|
}
|
|
--------------------------------------------------
|
|
|
|
<1> `bucket_paths` instructs this max_bucket aggregation that we want the maximum value of the `sales` aggregation in the
|
|
`sales_per_month` date histogram.
|
|
|
|
And the following may be the response:
|
|
|
|
[source,js]
|
|
--------------------------------------------------
|
|
{
|
|
"aggregations": {
|
|
"sales_per_month": {
|
|
"buckets": [
|
|
{
|
|
"key_as_string": "2015/01/01 00:00:00",
|
|
"key": 1420070400000,
|
|
"doc_count": 3,
|
|
"sales": {
|
|
"value": 550
|
|
}
|
|
},
|
|
{
|
|
"key_as_string": "2015/02/01 00:00:00",
|
|
"key": 1422748800000,
|
|
"doc_count": 2,
|
|
"sales": {
|
|
"value": 60
|
|
}
|
|
},
|
|
{
|
|
"key_as_string": "2015/03/01 00:00:00",
|
|
"key": 1425168000000,
|
|
"doc_count": 2,
|
|
"sales": {
|
|
"value": 375
|
|
}
|
|
}
|
|
]
|
|
},
|
|
"max_monthly_sales": {
|
|
"keys": ["2015/01/01 00:00:00"], <1>
|
|
"value": 550
|
|
}
|
|
}
|
|
}
|
|
--------------------------------------------------
|
|
|
|
<1> `keys` is an array of strings since the maximum value may be present in multiple buckets
|
|
|