Significance is related to the changes in document frequency observed between everyday use in the corpus and
frequency observed in the result set. The asciidocs include extensive details on the applications of this feature.
Closes#5146
This aggregation computes unique term counts using the hyperloglog++ algorithm
which uses linear counting to estimate low cardinalities and hyperloglog on
higher cardinalities.
Since this algorithm works on hashes, it is useful for high-cardinality fields
to store the hash of values directly in the index, which is the purpose of
the new `murmur3` field type. This is less necessary on low-cardinality
string fields because the aggregator is smart enough to only compute the hash
once per unique value per segment thanks to ordinals, or on numeric fields
since hashing them is very fast.
Close#5426
Supports sorting on sub-aggs down the current hierarchy. This is supported as long as the aggregation in the specified order path are of a single-bucket type, where the last aggregation in the path points to either a single-bucket aggregation or a metrics one. If it's a single-bucket aggregation, the sort will be applied on the document count in the bucket (i.e. doc_count), and if it is a metrics type, the sort will be applied on the pointed out metric (in case of a single-metric aggregations, such as avg, the sort will be applied on the single metric value)
NOTE: this commit adds a constraint on what should be considered a valid aggregation name. Aggregations names must be alpha-numeric and may contain '-' and '_'.
Closes#5253
Terms aggregations return up to `size` terms, so up to now, the way to get all
matching terms back was to set `size` to an arbitrary high number that would be
larger than the number of unique terms.
Terms aggregators already made sure to not allocate memory based on the `size`
parameter so this commit mostly consists in making `0` an alias for the
maximum integer value in the TermsParser.
Close#4837
* Make it clearer that `aggs` is an allowed synomym
for the `aggregations` key
* Fix broken example in for datehistogram, `1.5M` is
not an allowed interval
* Make use of colon before examples consistent
* Fix typos
`min_doc_count` is the minimum number of hits that a term or histogram key
should match in order to appear in the response.
`min_doc_count=0` replaces `compute_empty_buckets` for histograms and will
behave exactly like facets' `all_terms=true` for terms aggregations.
Close#4662
Added a long-based representation of GeoHashes to GeoHashUtils for fast evaluation in aggregations.
The new BucketUtils provides a common heuristic for determining the number of results to obtain from each shard in "top N" type requests.
When the ValuesSource has ordinals, terms ordinals are used as a cache key to
bucket ordinals. This can make terms aggregations on String terms significantly
faster.
Close#4350
markharwood
Boaz Leskes
rphadake
Adrien Grand
Benjamin Devèze
uboness
Zachary Tong
Binh Ly
Clinton Gormley
Jun Ohtani
Florian Gilcher
Dawid Weiss
Florian Schilling
Chris Simpson