Time series aggregation

The time series aggregation queries data created using a Time series data stream (TSDS). This is typically data such as metrics or other data streams with a time component, and requires creating an index using the time series mode.

Data can be added to the time series index like other indices:

PUT /my-time-series-index-0/_bulk
{ "index": {} }
{ "key": "a", "val": 1, "@timestamp": "2022-01-01T00:00:10Z" }
{ "index": {}}
{ "key": "a", "val": 2, "@timestamp": "2022-01-02T00:00:00Z" }
{ "index": {} }
{ "key": "b", "val": 2, "@timestamp": "2022-01-01T00:00:10Z" }
{ "index": {}}
{ "key": "b", "val": 3, "@timestamp": "2022-01-02T00:00:00Z" }

To perform a time series aggregation, specify "time_series" as the aggregation type. When the boolean "keyed" is true (the default), each bucket is given a unique key.

GET /_search
{
  "aggs": {
    "ts": {
      "time_series": { "keyed": false }
    }
  }
}

This will return all results in the time series, however a more typical query will use sub aggregations to reduce the date returned to something more relevant.

By default, time series aggregations return 10000 results. The "size" parameter can be used to limit the results further. Alternatively, using sub aggregations can limit the amount of values returned as a time series aggregation.

The keyed parameter determines if buckets are returned as a map with unique keys per bucket. By default (keyed set to true), buckets are returned as a map. When keyed is false, buckets are returned as an array.

The time_series aggregation has many limitations, and we recommend that you do not use it. It turns off many aggregation performance optimizations, and it fails or behaves differently when you combine it with other aggregations, for example composite, global, top_hits, rare_terms, auto_date_histogram and the sampler aggregations. Use the ES|QL TS command instead.