Aggregate metric field type
editAggregate metric field type
editStores pre-aggregated numeric values for metric
aggregations. An aggregate_metric_double
field is an object containing one
or more of the following metric sub-fields: min
, max
, sum
, and
value_count
.
When you run certain metric aggregations on an aggregate_metric_double
field,
the aggregation uses the related sub-field’s values. For example, a
min
aggregation on an
aggregate_metric_double
field returns the minimum value of all min
sub-fields.
An aggregate_metric_double
field stores a single numeric
doc value for each metric sub-field. Array values are not
supported. min
, max
, and sum
values are double
numbers. value_count
is a positive long
number.
response = client.indices.create( index: 'my-index', body: { mappings: { properties: { "my-agg-metric-field": { type: 'aggregate_metric_double', metrics: [ 'min', 'max', 'sum', 'value_count' ], default_metric: 'max' } } } } ) puts response
PUT my-index { "mappings": { "properties": { "my-agg-metric-field": { "type": "aggregate_metric_double", "metrics": [ "min", "max", "sum", "value_count" ], "default_metric": "max" } } } }
Parameters for aggregate_metric_double
fields
edit-
metrics
-
(Required, array of strings)
Array of metric sub-fields to store. Each value corresponds to a
metric aggregation. Valid values are
min
,max
,sum
, andvalue_count
. You must specify at least one value. -
default_metric
-
(Required, string)
Default metric sub-field to use for queries, scripts, and aggregations that
don’t use a sub-field. Must be a value from the
metrics
array. -
time_series_metric
-
(Optional, string) Marks the field as a time series metric. The value is the metric type. You can’t update this parameter for existing fields.
Valid
time_series_metric
values foraggregate_metric_double
fields-
gauge
- A metric that represents a single numeric that can arbitrarily increase or decrease. For example, a temperature or available disk space.
-
null
(Default) - Not a time series metric.
-
Uses
editWe designed aggregate_metric_double
fields for use with the following aggregations:
-
A
min
aggregation returns the minimum value of allmin
sub-fields. -
A
max
aggregation returns the maximum value of allmax
sub-fields. -
A
sum
aggregation returns the sum of the values of allsum
sub-fields. -
A
value_count
aggregation returns the sum of the values of allvalue_count
sub-fields. -
A
avg
aggregation. There is noavg
sub-field; the result of theavg
aggregation is computed using thesum
andvalue_count
metrics. To run anavg
aggregation, the field must contain bothsum
andvalue_count
metric sub-field.
Running any other aggregation on an aggregate_metric_double
field will fail with
an "unsupported aggregation" error.
Finally, an aggregate_metric_double
field supports the following queries for which
it behaves as a double
by delegating its behavior to its default_metric
sub-field:
Examples
editThe following create index API request creates an
index with an aggregate_metric_double
field named agg_metric
. The request
sets max
as the field’s default_metric
.
response = client.indices.create( index: 'stats-index', body: { mappings: { properties: { agg_metric: { type: 'aggregate_metric_double', metrics: [ 'min', 'max', 'sum', 'value_count' ], default_metric: 'max' } } } } ) puts response
PUT stats-index { "mappings": { "properties": { "agg_metric": { "type": "aggregate_metric_double", "metrics": [ "min", "max", "sum", "value_count" ], "default_metric": "max" } } } }
The following index API request adds documents with
pre-aggregated data in the agg_metric
field.
response = client.index( index: 'stats-index', id: 1, body: { agg_metric: { min: -302.5, max: 702.3, sum: 200, value_count: 25 } } ) puts response response = client.index( index: 'stats-index', id: 2, body: { agg_metric: { min: -93, max: 1702.3, sum: 300, value_count: 25 } } ) puts response
PUT stats-index/_doc/1 { "agg_metric": { "min": -302.50, "max": 702.30, "sum": 200.0, "value_count": 25 } } PUT stats-index/_doc/2 { "agg_metric": { "min": -93.00, "max": 1702.30, "sum": 300.00, "value_count": 25 } }
You can run min
, max
, sum
, value_count
, and avg
aggregations on a
agg_metric
field.
response = client.search( index: 'stats-index', size: 0, body: { aggregations: { metric_min: { min: { field: 'agg_metric' } }, metric_max: { max: { field: 'agg_metric' } }, metric_value_count: { value_count: { field: 'agg_metric' } }, metric_sum: { sum: { field: 'agg_metric' } }, metric_avg: { avg: { field: 'agg_metric' } } } } ) puts response
POST stats-index/_search?size=0 { "aggs": { "metric_min": { "min": { "field": "agg_metric" } }, "metric_max": { "max": { "field": "agg_metric" } }, "metric_value_count": { "value_count": { "field": "agg_metric" } }, "metric_sum": { "sum": { "field": "agg_metric" } }, "metric_avg": { "avg": { "field": "agg_metric" } } } }
The aggregation results are based on related metric sub-field values.
{ ... "aggregations": { "metric_min": { "value": -302.5 }, "metric_max": { "value": 1702.3 }, "metric_value_count": { "value": 50 }, "metric_sum": { "value": 500.0 }, "metric_avg": { "value": 10.0 } } }
Queries on a aggregate_metric_double
field use the default_metric
value.
response = client.search( index: 'stats-index', body: { query: { term: { agg_metric: { value: 702.3 } } } } ) puts response
GET stats-index/_search { "query": { "term": { "agg_metric": { "value": 702.30 } } } }
The search returns the following hit. The value of the default_metric
field,
max
, matches the query value.
{ ... "hits": { "total": { "value": 1, "relation": "eq" }, "max_score": 1.0, "hits": [ { "_index": "stats-index", "_id": "1", "_score": 1.0, "_source": { "agg_metric": { "min": -302.5, "max": 702.3, "sum": 200.0, "value_count": 25 } } } ] } }
Synthetic _source
editSynthetic _source
is Generally Available only for TSDB indices
(indices that have index.mode
set to time_series
). For other indices
synthetic _source
is in technical preview. Features in technical preview may
be changed or removed in a future release. Elastic will apply best effort to fix
any issues, but features in technical preview are not subject to the support SLA
of official GA features.
aggregate_metric-double
fields support synthetic _source
in their default
configuration. Synthetic _source
cannot be used together with ignore_malformed
.
For example:
PUT idx { "mappings": { "_source": { "mode": "synthetic" }, "properties": { "agg_metric": { "type": "aggregate_metric_double", "metrics": [ "min", "max", "sum", "value_count" ], "default_metric": "max" } } } } PUT idx/_doc/1 { "agg_metric": { "min": -302.50, "max": 702.30, "sum": 200.0, "value_count": 25 } }
Will become:
{ "agg_metric": { "min": -302.50, "max": 702.30, "sum": 200.0, "value_count": 25 } }