We used to set `maxScore` to `0` within `TopDocs` in situations where there is really no score as the size was set to `0` and scores were not even tracked. In such scenarios, `Float.Nan` is more appropriate, which gets converted to `max_score: null` on the REST layer. That's also more consistent with lucene which set `maxScore` to `Float.Nan` when merging empty `TopDocs` (see `TopDocs#merge`).
This commit changes the default out-of-the-box configuration for the
number of shards from five to one. We think this will help address a
common problem of oversharding. For users with time-based indices that
need a different default, this can be managed with index templates. For
users with non-time-based indices that find they need to re-shard with
the split API in place they no longer need to resort only to
reindexing.
Since this has the impact of changing the default number of shards used
in REST tests, we want to ensure that we still have coverage for issues
that could arise from multiple shards. As such, we randomize (rarely)
the default number of shards in REST tests to two. This is managed via a
global index template. However, some tests check the templates that are
in the cluster state during the test. Since this template is randomly
there, we need a way for tests to skip adding the template used to set
the number of shards to two. For this we add the default_shards feature
skip. To avoid having to write our docs in a complicated way because
sometimes they might be behind one shard, and sometimes they might be
behind two shards we apply the default_shards feature skip to all docs
tests. That is, these tests will always run with the default number of
shards (one).
Allowing `_doc` as a type will enable users to make the transition to 7.0
smoother since the index APIs will be `PUT index/_doc/id` and `POST index/_doc`.
This also moves most of the documentation to `_doc` as a type name.
Closes#27750Closes#27751
This change exposes the duplicate removal option added in Lucene for the completion suggester
with a new option called `skip_duplicates` (defaults to false).
This commit also adapts the custom suggest collector to handle deduplication when multiple contexts match the input.
Closes#23364
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.
* Replace _suggest endpoint to _search in docs
In 5.0, the _suggest endpoint is just sugar for _search
with suggestions specified. Users should move away from
using the _suggest endpoint, as it is marked as deprecated in 5.x and
will be removed in 6.0
* update docs to use _search endpoint instead of _suggest
* Add deprecation logging to RestSuggestAction
* Use search endpoint instead of suggest endpoint in rest tests
We plan to deprecate `_suggest` during 5.0 so it isn't worth fixing
it to support the `_source` parameter for `_source` filtering. But we
should fix the docs so they are accurate.
Since this removes the last non-`// CONSOLE` line in
`completion-suggest.asciidoc` this also removes it from the list of
files that have non-`// CONSOLE` docs.
Closes#20482
The payload option was introduced with the new completion
suggester implementation in v5, as a stop gap solution
to return additional metadata with suggestions.
Now we can return associated documents with suggestions
(#19536) through fetch phase using stored field (_source).
The additional fetch phase ensures that we only fetch
the _source for the global top-N suggestions instead of
fetching _source of top results for each shard.
This commit enables completion suggester to return documents
associated with suggestions. Now the document source is returned
with every suggestion, which respects source filtering options.
In case of suggest queries spanning more than one shard, the
suggest is executed in two phases, where the last phase fetches
the relevant documents from shards, implying executing suggest
requests against a single shard is more performant due to the
document fetch overhead when the suggest spans multiple shards.
The completion suggester provides auto-complete/search-as-you-type functionality.
This is a navigational feature to guide users to relevant results as they are typing, improving search precision.
It is not meant for spell correction or did-you-mean functionality like the term or phrase suggesters.
The completions are indexed as a weighted FST (finite state transducer) to provide fast Top N prefix-based
searches suitable for serving relevant results as a user types.
closes#10746
The `analyzer` setting is now the base setting, and `search_analyzer`
is simply an override of the search time analyzer. When setting
`search_analyzer`, `analyzer` must be set.
closes#9371
The existing Note about the shorthand suggest syntax was poorly worded and confusing. Please check whether the way I've phrased it now is still correct as to what the shorthand form actually does and doesn't do: the original wording did not provide me enough information to be sure.
Thanks!
================
This commit extends the `CompletionSuggester` by context
informations. In example such a context informations can
be a simple string representing a category reducing the
suggestions in order to this category.
Three base implementations of these context informations
have been setup in this commit.
- a Category Context
- a Geo Context
All the mapping for these context informations are
specified within a context field in the completion
field that should use this kind of information.
Java Builder apis drop old “len” methods in favour of new “length”
Rest APIs support both old “len: and new “length” forms using new ParseField class to a) provide compiler-checked consistency between Builder and Parser classes and
b) a common means of handling deprecated syntax in the DSL.
Documentation and rest specs only document the new “*length” forms
Closes#4083
When upgrading to ES 1.0 the existing mappings with a multi-field type automatically get replaced to a core field with the new `fields` option.
If a `multi_field` type-ed field doesn't have a main / default field, a default field will be chosen for the multi fields syntax. The new main field type
will be equal to the first `multi_field` fields' field or type string if no fields have been configured for the `multi_field` field and in both cases
the default index will not be indexed (`index=no` is set on the default field).
If a `multi_field` typed field has a default field, that field will replace the `multi_field` typed field.
Closes to #4521
A lot of different API's currently use different names for the
same logical parameter. Since lucene moved away from the notion
of a `similarity` and now uses an `fuzziness` we should generalize
this and encapsulate the generation, parsing and creation of these
settings across all queries.
This commit adds a new `Fuzziness` class that handles the renaming
and generalization in a backwards compatible manner.
This commit also added a ParseField class to better support deprecated
Query DSL parameters
The ParseField class allows specifying parameger that have been deprecated.
Those parameters can be more easily tracked and removed in future version.
This also allows to run queries in `strict` mode per index to throw
exceptions if a query is executed with deprected keys.
Closes#4082
This contribution is based on the feedback given in issue #4254 and
issue #4255, and should clear things up, when suggestions are being
removed and not displayed anymore after deletion of data.
* Minor alignments (like setter to ctor)
* FuzzySuggester has a unicode aware flag, which is not exposed in the fuzzy completion request parameters
* Made XAnalyzingSuggester flags (PAYLOAD_SEP, END_BYTE, SEP_LABEL) to be written into the postings format, so we can retain backwards compatibility
* The above change also implies, that these flags can be set per instantiated XAnalyzingSuggester
* CompletionPostingsFormatTest now uses a randomProvider for writing data to check for bwc
Restrict the size of the input length to a reasonable size otherwise very
long strings can cause StackOverflowExceptions deep down in lucene land.
Yet, this is simply a saftly limit set to `50` UTF-16 codepoints by default.
This limit is only present at index time and not at query time. If prefix
completions > 50 UTF-16 codepoints are expected / desired this limit should be raised.
Critical string sizes are beyone the 1k UTF-16 Codepoints limit.
Closes#3596