The aggregations in this family compute metrics based on values extracted in one way or another from the documents that are being aggregated. The values are typically extracted from the fields of the document (using the field data), but can also be generated using scripts.
See the Elasticsearch documentation on {ref_current}/search-aggregations-metrics.html[Metric aggregations] for more details.
Bucket aggregations don’t calculate metrics over fields like the metrics aggregations do, but instead, they create buckets of documents. Each bucket is associated with a criterion (depending on the aggregation type) which determines whether or not a document in the current context "falls" into it. In other words, the buckets effectively define document sets. In addition to the buckets themselves, the bucket aggregations also compute and return the number of documents that "fell into" each bucket.
|
Note
|
Bucketing aggregations can have sub-aggregations (bucketing or metric). The sub-aggregations will be computed for the buckets which their parent aggregation generates. There is no hard limit on the level/depth of nested aggregations (one can nest an aggregation under a "parent" aggregation, which is itself a sub-aggregation of another higher-level aggregation). |
See the Elasticsearch documentation on {ref_current}/search-aggregations-bucket.html[Bucket aggregations] for more details.
Pipeline aggregations work on the outputs produced from other aggregations rather than from document sets, adding information to the output tree. There are many different types of pipeline aggregation, each computing different information from other aggregations.
See the Elasticsearch documentation on {ref_current}/search-aggregations-pipeline.html[Pipeline aggregations] for more details.
The aggregations in this family operate on multiple fields and produce a matrix result based on the values extracted from the requested document fields. Unlike metric and bucket aggregations, this aggregation family does not yet support scripting.
See the Elasticsearch documentation on {ref_current}/search-aggregations-matrix.html[Matrix aggregations] for more details.