Today if we search across a large amount of shards we hit every shard. Yet, it's quite
common to search across an index pattern for time based indices but filtering will exclude
all results outside a certain time range ie. `now-3d`. While the search can potentially hit
hundreds of shards the majority of the shards might yield 0 results since there is not document
that is within this date range. Kibana for instance does this regularly but used `_field_stats`
to optimize the indexes they need to query. Now with the deprecation of `_field_stats` and it's upcoming removal a single dashboard in kibana can potentially turn into searches hitting hundreds or thousands of shards and that can easily cause search rejections even though the most of the requests are very likely super cheap and only need a query rewriting to early terminate with 0 results.
This change adds a pre-filter phase for searches that can, if the number of shards are higher than a the `pre_filter_shard_size` threshold (defaults to 128 shards), fan out to the shards
and check if the query can potentially match any documents at all. While false positives are possible, a negative response means that no matches are possible. These requests are not subject to rejection and can greatly reduce the number of shards a request needs to hit. The approach here is preferable to the kibana approach with field stats since it correctly handles aliases and uses the correct threadpools to execute these requests. Further it's completely transparent to the user and improves scalability of elasticsearch in general on large clusters.
* [Analysis] Parse synonyms with the same analysis chain
Synonym Token Filter / Synonym Graph Filter tokenize synonyms with whatever tokenizer and token filters appear before it in the chain.
Close#7199
This snapshot has faster range queries on range fields (LUCENE-7828), more
accurate norms (LUCENE-7730) and the ability to use fake term frequencies
(LUCENE-7854).
Expose the experimental simplepattern and
simplepatternsplit tokenizers in the common
analysis plugin. They provide tokenization based
on regular expressions, using Lucene's
deterministic regex implementation that is usually
faster than Java's and has protections against
creating too-deep stacks during matching.
Both have a not-very-useful default pattern of the
empty string because all tokenizer factories must
be able to be instantiated at index creation time.
They should always be configured by the user
in practice.
This adds the `index.mapping.single_type` setting, which enforces that indices
have at most one type when it is true. The default value is true for 6.0+ indices
and false for old indices.
Relates #15613
Converts the analysis docs to that were marked as json into `CONSOLE`
format. A few of them were in yaml but marked as json for historical
reasons. I added more complete examples for a few of the less obvious
sounding ones.
Relates to #18160
The pattern-analyzer docs contained a snippet that was an expanded
regex that was marked as `[source,js]`. This changes it to
`[source,regex]`.
The htmlstrip-charfilter and pattern-replace-charfilter docs had
examples that were actually a list of tokens but marked `[source,js]`.
This marks them as `[source,text]` so they don't count as unconverted
CONSOLE snippets.
The pattern-replace-charfilter also had a doc who's test was
skipped because of funny interaction with the test framework. This
fixes the test.
Three more down, eighty-two to go.
Relates to #18160
CONSOLEifies the lang-analyzer docs and replaces the (invalid)
empty `keyword_marker` setups that were on the page with one
that contains the word "example" translated into the appropriate
language.
Relates to #18160
This commit adds support for the pattern keyword marker filter in
Lucene. Previously, the keyword marker filter in Elasticsearch
supported specifying a keywords set or a path to a set of keywords.
This commit exposes the regular expression pattern based keyword marker
filter also available in Lucene, so that any token matching the pattern
specified by the `keywords_pattern` setting is excluded from being
stemmed by any stemming filters.
Closes#4877
This change exposes the new Lucene graph based word delimiter token filter in the analysis filters.
Unlike the `word_delimiter` this token filter named `word_delimiter_graph` correctly handles multi terms expansion at query time.
Closes#23104
This PR removes all leniency in the conversion of Strings to booleans: "true"
is converted to the boolean value `true`, "false" is converted to the boolean
value `false`. Everything else raises an error.
This adds a new `normalizer` property to `keyword` fields that pre-processes the
field value prior to indexing, but without altering the `_source`. Note that
only the normalization components that work on a per-character basis are
applied, so for instance stemming filters will be ignored while lowercasing or
ascii folding will be applied.
Closes#18064
* Repeated language analyzers
The `catalan` analyzer was repeated on the supported list :)
* Reordered the languages to have alphabetic order
* Added space for format
* Reordered the languages and removed repeated
Integrate the patch from LUCENE-6664 into elasticsearch and
add support for handling a graph token stream in match/multi-match
queries.
This fixes longstanding bugs with multi-token synonyms returning
incorrect results with proximity queries.
Exposing lucene 6.x minhash tokenfilter
Generate min hash tokens from an incoming stream of tokens that can
be used to estimate document similarity.
Closes#20149
This change adds a special field named _none_ that allows to disable the retrieval of the stored fields in a search request or in a TopHitsAggregation.
To completely disable stored fields retrieval (including disabling metadata fields retrieval such as _id or _type) use _none_ like this:
````
POST _search
{
"stored_fields": "_none_"
}
````
* Docs: Improved tokenizer docs
Added descriptions and runnable examples
* Addressed Nik's comments
* Added TESTRESPONSEs for all tokenizer examples
* Added TESTRESPONSEs for all analyzer examples too
* Added docs, examples, and TESTRESPONSES for character filters
* Skipping two tests:
One interprets "$1" as a stack variable - same problem exists with the REST tests
The other because the "took" value is always different
* Fixed tests with "took"
* Fixed failing tests and removed preserve_original from fingerprint analyzer
Rearranges the FingerprintAnalyzer so that AsciiFolding comes earlier in the chain (after lowercasing, before stop removal, for maximum deduping power)
Closes#18266
Clinton Gormley
Neil Rickards
Simon Willnauer
Jun Ohtani
Andy Bristol
debadair
Adrien Grand
Jim Ferenczi
Nik Everett
Abdon Pijpelink
Ali Beyad
Jim Ferenczi
markwalkom
Shubham Aggarwal
Daniel Mitterdorfer
Michael McCandless
Matt Weber
Achraf
Francesc Gil
Thibault Pierre
Allen Torres
Pascal Borreli
Alexander Lin
Zachary Tong