83 lines
2.3 KiB
Plaintext
83 lines
2.3 KiB
Plaintext
[[search-aggregations-metrics-valuecount-aggregation]]
|
|
=== Value Count Aggregation
|
|
|
|
A `single-value` metrics aggregation that counts the number of values that are extracted from the aggregated documents.
|
|
These values can be extracted either from specific fields in the documents, or be generated by a provided script. Typically,
|
|
this aggregator will be used in conjunction with other single-value aggregations. For example, when computing the `avg`
|
|
one might be interested in the number of values the average is computed over.
|
|
|
|
[source,js]
|
|
--------------------------------------------------
|
|
POST /sales/_search?size=0
|
|
{
|
|
"aggs" : {
|
|
"types_count" : { "value_count" : { "field" : "type" } }
|
|
}
|
|
}
|
|
--------------------------------------------------
|
|
// CONSOLE
|
|
// TEST[setup:sales]
|
|
|
|
Response:
|
|
|
|
[source,js]
|
|
--------------------------------------------------
|
|
{
|
|
...
|
|
"aggregations": {
|
|
"types_count": {
|
|
"value": 7
|
|
}
|
|
}
|
|
}
|
|
--------------------------------------------------
|
|
// TESTRESPONSE[s/\.\.\./"took": $body.took,"timed_out": false,"_shards": $body._shards,"hits": $body.hits,/]
|
|
|
|
The name of the aggregation (`types_count` above) also serves as the key by which the aggregation result can be
|
|
retrieved from the returned response.
|
|
|
|
==== Script
|
|
|
|
Counting the values generated by a script:
|
|
|
|
[source,js]
|
|
--------------------------------------------------
|
|
POST /sales/_search?size=0
|
|
{
|
|
"aggs" : {
|
|
"type_count" : {
|
|
"value_count" : {
|
|
"script" : {
|
|
"source" : "doc['type'].value"
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
--------------------------------------------------
|
|
// CONSOLE
|
|
// TEST[setup:sales]
|
|
|
|
This will interpret the `script` parameter as an `inline` script with the `painless` script language and no script parameters. To use a stored script use the following syntax:
|
|
|
|
[source,js]
|
|
--------------------------------------------------
|
|
POST /sales/_search?size=0
|
|
{
|
|
"aggs" : {
|
|
"types_count" : {
|
|
"value_count" : {
|
|
"script" : {
|
|
"id": "my_script",
|
|
"params" : {
|
|
"field" : "type"
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
--------------------------------------------------
|
|
// CONSOLE
|
|
// TEST[setup:sales,stored_example_script]
|