This change adds the recall@k metric and refactors precision@k to match
the new metric.
Recall@k is an important metric to use for learning to rank (LTR)
use-cases. Candidate generation or first ranking phase ranking functions
are often optimized for high recall, in order to generate as many
relevant candidates in the top-k as possible for a second phase of
ranking. Adding this metric allows tuning that base query for LTR.
See: https://github.com/elastic/elasticsearch/issues/51676
Backports: https://github.com/elastic/elasticsearch/pull/52577
* Adds an example request to the top of the page.
* Relocates several parameters erroneously listed under "Request body"
to the appropriate "Query parameters" section.
* Updates the "Request body" section to better document the NDJSON
structure of msearch requests.
Add default value to each one of the usages of `allow_no_indices`
since it differs between different APIs.
Relates to: #52534
(cherry picked from commit 2eb986488ac326d6da6ab8ad0203a94e08684a36)
This PR adds per-field metadata that can be set in the mappings and is later
returned by the field capabilities API. This metadata is completely opaque to
Elasticsearch but may be used by tools that index data in Elasticsearch to
communicate metadata about fields with tools that then search this data. A
typical example that has been requested in the past is the ability to attach
a unit to a numeric field.
In order to not bloat the cluster state, Elasticsearch requires that this
metadata be small:
- keys can't be longer than 20 chars,
- values can only be numbers or strings of no more than 50 chars - no inner
arrays or objects,
- the metadata can't have more than 5 keys in total.
Given that metadata is opaque to Elasticsearch, field capabilities don't try to
do anything smart when merging metadata about multiple indices, the union of
all field metadatas is returned.
Here is how the meta might look like in mappings:
```json
{
"properties": {
"latency": {
"type": "long",
"meta": {
"unit": "ms"
}
}
}
}
```
And then in the field capabilities response:
```json
{
"latency": {
"long": {
"searchable": true,
"aggreggatable": true,
"meta": {
"unit": [ "ms" ]
}
}
}
}
```
When there are no conflicts, values are arrays of size 1, but when there are
conflicts, Elasticsearch includes all unique values in this array, without
giving ways to know which index has which metadata value:
```json
{
"latency": {
"long": {
"searchable": true,
"aggreggatable": true,
"meta": {
"unit": [ "ms", "ns" ]
}
}
}
}
```
Closes#33267
PR #44238 changed several links related to the Elasticsearch search request body API. This updates several places still using outdated links or anchors.
This will ultimately let us remove some redirects related to those link changes.
File scripts were removed in 6.0 with #24627.
This removes an outdated file scripts reference from the conditional clauses section of the search templates docs.
This rewrites long sort as a `DistanceFeatureQuery`, which can
efficiently skip non-competitive blocks and segments of documents.
Depending on the dataset, the speedups can be 2 - 10 times.
The optimization can be disabled with setting the system property
`es.search.rewrite_sort` to `false`.
Optimization is skipped when an index has 50% or more data with
the same value.
Optimization is done through:
1. Rewriting sort as `DistanceFeatureQuery` which can
efficiently skip non-competitive blocks and segments of documents.
2. Sorting segments according to the primary numeric sort field(#44021)
This allows to skip non-competitive segments.
3. Using collector manager.
When we optimize sort, we sort segments by their min/max value.
As a collector expects to have segments in order,
we can not use a single collector for sorted segments.
We use collectorManager, where for every segment a dedicated collector
will be created.
4. Using Lucene's shared TopFieldCollector manager
This collector manager is able to exchange minimum competitive
score between collectors, which allows us to efficiently skip
the whole segments that don't contain competitive scores.
5. When index is force merged to a single segment, #48533 interleaving
old and new segments allows for this optimization as well,
as blocks with non-competitive docs can be skipped.
Backport for #48804
Co-authored-by: Jim Ferenczi <jim.ferenczi@elastic.co>
All document scores are positive 32-bit floating point numbers. However, this
wasn't previously documented.
This can result in surprising behavior, such as precision loss, for users when
customizing scores using the function score query.
This commit updates an existing admonition in the function score query docs to
document the 32-bits precision limit. It also updates the search API reference
docs to note that `_score` is a 32-bit float.
Customers occasionally discover a known behavior in Elasticsearch's pagination that does not appear to be documented. This warning is intended to educate customers of this behavior while still highlighting alternative solutions.
* [DOCS] Add template docs to scripts. Reorder template examples.
* Adds a 'Search template' section to the 'How to use scripts' chapter.
This links to the 'Search template' chapter for detailed info and
examples.
* Reorders and retitles several examples in the 'Search template'
chapter. This is primarily to make examples for storing, deleting, and
using search templates more prominent.
* Change <templatename> to <templateid>
Several files in the REST APIs nav section are included using
:leveloffset: tags. This increments headings (h2 -> h3, h3 -> h4, etc.)
in those files and removes the :leveloffset: tags.
Other supporting changes:
* Alphabetizes top-level REST API nav items.
* Change 'indices APIs' heading to 'index APIs.'
* Changes 'Snapshot lifecycle management' heading to sentence case.
Moves the following API sections under the REST APIs navigations:
- API Conventions
- Document APIs
- Search APIs
- Index APIs (previously named Indices APIs)
- cat APIs
- Cluster APIs
Other supporting changes:
- Removes the previous index APIs page under REST APIs. Adds a redirect for the removed page.
- Removes several [partintro] macros so the docs build correctly.
- Changes anchors for pages that become sections of a parent page.
- Adds several redirects for existing pages that become sections of a parent page.
This commit re-applies changes from #44238. Changes from that PR were reverted due to broken links in several repos. This commit adds redirects for those broken links.
the geo-bounding-box and phrase-suggest docs were susceptible to
failing due to other indices in the cluster. This change restricts
the queries to the index that is set up for the test.
relates to #43271.
Adding notes to the existing docs about how using `preference` might increase
request cache utilization but also add warning about the downsides.
Closes#24278
This PR updates the docs for `docvalue_fields` and `stored_fields` to clarify
that nested fields must be accessed through `inner_hits`. It also tweaks the
nested fields documentation to make this point more visible.
Addresses #23766.
Today the `_field_caps` API returns the list of indices where a field
is present only if this field has different types within the requested indices.
However if the request is an index pattern (or an alias, or both...) there
is no way to infer the indices if the response contains only fields that have
the same type in all indices. This commit changes the response to always return
the list of indices in the response. It also adds a way to retrieve unmapped field
in a specific section per field called `unmapped`. This section is created for each field
that is present in some indices but not all if the parameter `include_unmapped` is set to
true in the request (defaults to false).
Currently enabling profiling disables top-hits optimizations, which is
unfortunate: it would be nice to be able to notice the difference in method
counts and timings depending on whether total hit counts are requested.
The explanation given in the completion suggester documentation why we use the
"simple" analyzer as the default is no longer valid. Since we still use "simple"
as the default, we should just delete the explanation that doesn't fit anymore.
Closes#36715
Adds the search_as_you_type field type that acts like a text field optimized
for as-you-type search completion. It creates a couple subfields that analyze
the indexed terms as shingles, against which full terms are queried, and a
prefix subfield that analyze terms as the largest shingle size used and
edge-ngrams, against which partial terms are queried
Adds a match_bool_prefix query type that creates a boolean clause of a term
query for each term except the last, for which a boolean clause with a prefix
query is created.
The match_bool_prefix query is the recommended way of querying a search as you
type field, which will boil down to term queries for each shingle of the input
text on the appropriate shingle field, and the final (possibly partial) term
as a term query on the prefix field. This field type also supports phrase and
phrase prefix queries however
This change adds an option to convert a `date` field to nanoseconds resolution
and a `date_nanos` field to millisecond resolution when sorting.
The resolution of the sort can be set using the `numeric_type` option of the
field sort builder. The conversion is done at the shard level and is restricted
to dates from 1970 to 2262 for the nanoseconds resolution in order to avoid
numeric overflow.
This change adds an option to the `FieldSortBuilder` that allows to transform the type
of a numeric field into another. Possible values for this option are `long` that transforms
the source field into an integer and `double` that transforms the source field into a floating point.
This new option is useful for cross-index search when the sort field is mapped differently on some
indices. For instance if a field is mapped as a floating point in one index and as an integer in another
it is possible to align the type for both indices using the `numeric_type` option:
```
{
"sort": {
"field": "my_field",
"numeric_type": "double" <1>
}
}
```
<1> Ensure that values for this field are transformed to a floating point if needed.
Coalesces two calls into one in a scroll example so all callouts are at
the end of the line. This is the only sort of callouts that are
supported by asciidoctor and we'd like to start building our docs with
asciidoctor.
At present we don't have any mechanism to stop folks adding more inline
callouts but we ought to be able to have one in a few weeks. For now,
though, removing these inline callouts is a step in the right direction.
Relates to #38335
With #37566 we have introduced the ability to merge multiple search responses into one. That makes it possible to expose a new way of executing cross-cluster search requests, that makes CCS much faster whenever there is network latency between the CCS coordinating node and the remote clusters. The coordinating node can now send a single search request to each remote cluster, which gets reduced by each one of them. from + size results are requested to each cluster, and the reduce phase in each cluster is non final (meaning that buckets are not pruned and pipeline aggs are not executed). The CCS coordinating node performs an additional, final reduction, which produces one search response out of the multiple responses received from the different clusters.
This new execution path will be activated by default for any CCS request unless a scroll is provided or inner hits are requested as part of field collapsing. The search API accepts now a new parameter called ccs_minimize_roundtrips that allows to opt-out of the default behaviour.
Relates to #32125
Doc-value fields now return a value that is based on the mappings rather than
the script implementation by default.
This deprecates the special `use_field_mapping` docvalue format which was added
in #29639 only to ease the transition to 7.x and it is not necessary anymore in
7.0.
This commit changes the default for the `track_total_hits` option of the search request
to `10,000`. This means that by default search requests will accurately track the total hit count
up to `10,000` documents, requests that match more than this value will set the `"total.relation"`
to `"gte"` (e.g. greater than or equals) and the `"total.value"` to `10,000` in the search response.
Scroll queries are not impacted, they will continue to count the total hits accurately.
The default is set back to `true` (accurate hit count) if `rest_total_hits_as_int` is set in the search request.
I choose `10,000` as the default because that's also the number we use to limit pagination. This means that users will be able to know how far they can jump (up to 10,000) even if the total number of hits is not accurate.
Closes#33028
Users may require the sequence number and primary terms to perform optimistic concurrency control operations. Currently, you can get the sequence number via the `docvalues_fields` API but the primary term is not accessible because it is maintained by the `SeqNoFieldMapper` and the infrastructure can't find it.
This commit adds a dedicated sub fetch phase to return both numbers that is connected to a new `seq_no_primary_term` parameter.
The "include_type_name" parameter was temporarily introduced in #37285 to facilitate
moving the default parameter setting to "false" in many places in the documentation
code snippets. Most of the places can simply be reverted without causing errors.
In this change I looked for asciidoc files that contained the
"include_type_name=true" addition when creating new indices but didn't look
likey they made use of the "_doc" type for mappings. This is mostly the case
e.g. in the analysis docs where index creating often only contains settings. I
manually corrected the use of types in some places where the docs still used an
explicit type name and not the dummy "_doc" type.
* Default include_type_name to false for get and put mappings.
* Default include_type_name to false for get field mappings.
* Add a constant for the default include_type_name value.
* Default include_type_name to false for get and put index templates.
* Default include_type_name to false for create index.
* Update create index calls in REST documentation to use include_type_name=true.
* Some minor clean-ups around the get index API.
* In REST tests, use include_type_name=true by default for index creation.
* Make sure to use 'expression == false'.
* Clarify the different IndexTemplateMetaData toXContent methods.
* Fix FullClusterRestartIT#testSnapshotRestore.
* Fix the ml_anomalies_default_mappings test.
* Fix GetFieldMappingsResponseTests and GetIndexTemplateResponseTests.
We make sure to specify include_type_name=true during xContent parsing,
so we continue to test the legacy typed responses. XContent generation
for the typeless responses is currently only covered by REST tests,
but we will be adding unit test coverage for these as we implement
each typeless API in the Java HLRC.
This commit also refactors GetMappingsResponse to follow the same appraoch
as the other mappings-related responses, where we read include_type_name
out of the xContent params, instead of creating a second toXContent method.
This gives better consistency in the response parsing code.
* Fix more REST tests.
* Improve some wording in the create index documentation.
* Add a note about types removal in the create index docs.
* Fix SmokeTestMonitoringWithSecurityIT#testHTTPExporterWithSSL.
* Make sure to mention include_type_name in the REST docs for affected APIs.
* Make sure to use 'expression == false' in FullClusterRestartIT.
* Mention include_type_name in the REST templates docs.
In Lucene 8 searches can skip non-competitive hits if the total hit count is not requested.
It is also possible to track the number of hits up to a certain threshold. This is a trade off to speed up searches while still being able to know a lower bound of the total hit count. This change adds the ability to set this threshold directly in the track_total_hits search option. A boolean value (true, false) indicates whether the total hit count should be tracked in the response. When set as an integer this option allows to compute a lower bound of the total hits while preserving the ability to skip non-competitive hits when enough matches have been collected.
Relates #33028
The following updates were made:
- Add a new untyped endpoint `{index}/_explain/{id}`.
- Add deprecation warnings to Rest*Action, plus tests in Rest*ActionTests.
- For each REST yml test, make sure there is one version without types, and another legacy version that retains types (called *_with_types.yml).
- Deprecate relevant methods on the Java HLRC requests/ responses.
- Update documentation (for both the REST API and Java HLRC).
This commit changes the format of the `hits.total` in the search response to be an object with
a `value` and a `relation`. The `value` indicates the number of hits that match the query and the
`relation` indicates whether the number is accurate (in which case the relation is equals to `eq`)
or a lower bound of the total (in which case it is equals to `gte`).
This change also adds a parameter called `rest_total_hits_as_int` that can be used in the
search APIs to opt out from this change (retrieve the total hits as a number in the rest response).
Note that currently all search responses are accurate (`track_total_hits: true`) or they don't contain
`hits.total` (`track_total_hits: true`). We'll add a way to get a lower bound of the total hits in a
follow up (to allow numbers to be passed to `track_total_hits`).
Relates #33028
This change adds a soft limit to open scroll contexts that can be controlled with the dynamic cluster setting `search.max_open_scroll_context` (defaults to 500).
Add a short extra sentence that explains that a missing query part in a search
request containing a "suggest" section will mean only suggestions are returned.
Closes#31640
* Deprecate types in count requests.
* Move RestCountAction to the 'search' package.
* Deprecate types in multi search requests.
* Add tests for types deprecation in the _search endpoint.
The documentation of `search_after` recommends to use the `_id`
field as a tiebreaker for the sort without warning against
the additional memory required. This change changes the recommandation
to use a copy of the `_id` field with doc_values enabled.
Deprecates `_source_include` and `_source_exclude` url parameters
in favor of `_source_inclues` and `_source_excludes` because those
are consistent with the rest of Elasticsearch's APIs.
Relates to #22792
* Replace custom type names with _doc in REST examples.
* Avoid using two mapping types in the percolator docs.
* Rename doc -> _doc in the main repository README.
* Also replace some custom type names in the HLRC docs.
This change clarifies the documentation of the context completion suggester
regarding filtering and boosting with contexts.
Unlike the suggester v1, filtering on multiple contexts
works as a disjunction, a suggestion matches if it contains at least one of the provided
context values and boosting selects the maximum score among the matching contexts.
This commit also adapts an old test that was written for the v1 suggester and commented out
for version 2 because the behavior changed.
The main benefit of the upgrade for users is the search optimization for top scored documents when the total hit count is not needed. However this optimization is not activated in this change, there is another issue opened to discuss how it should be integrated smoothly.
Some comments about the change:
* Tests that can produce negative scores have been adapted but we need to forbid them completely: #33309Closes#32899
Global search timeouts and timeouts specified in the search request body use the
same internal mechanism as search cancellation. Therefore the same caveats
apply, mostly around the responsiveness of the timeout which gets only checked
by a running search on segment boundaries by default.
Closes#31263
This commit adds the support to early terminate the collection of a leaf
in the aggregation framework. This change introduces a MultiBucketCollector which
handles CollectionTerminatedException exactly like the Lucene MultiCollector.
Any aggregator can now throw a CollectionTerminatedException without stopping
the collection of a sibling aggregator. This is useful for aggregators that
can infer their result without visiting all documents (e.g.: a min/max aggregation on a match_all query).
* Search: Support of wildcard on docvalue_fields
For consistency with stored_fields, docvalue_fields should support the use of wildcards.
Documentation of doc values fields is updated accordingly.
See also: #26390Closes#26299
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`).
Today `_msearch` doesn't allow modifying the `max_concurrent_shard_requests`
per sub search request. This change adds support for setting this parameter on
all sub-search requests in an `_msearch`.
Relates to #31877
The notion of "quality" is an overloaded term in the search ranking evaluation
context. Its usually used to decribe certain levels of "good" vs. "bad" of a
seach result with respect to the users information need. We currently report the
result of the ranking evaluation as `quality_level` which is a bit missleading.
This changes the response parameter name to `metric_score` which fits better.
Currently the ranking evaluation response contains a 'unknown_docs' section
for each search use case in the evaluation set. It contains document ids for
results in the search hits that currently don't have a quality rating.
This change renames it to `unrated_docs`, which better reflects its purpose.
Today it is unclear what guarantees are offered by the search preference
feature, and we claim a guarantee that is stronger than what we really offer:
> A custom value will be used to guarantee that the same shards will be used
> for the same custom value.
This commit clarifies this documentation.
Forward-port of #32098 to `master`.
Adds support for `ignore_unmapped` parameter in geo distance sorting,
which is functionally equivalent to specifying an `unmapped_type` in
the field sort.
Closes#28152
This change deprecates completion queries and documents without context that target a
context enabled completion field. Querying without context degrades the search
performance considerably (even when the number of indexed contexts is low).
This commit targets master but the deprecation will take place in 6.x and the functionality
will be removed in 7 in a follow up.
Closes#29222
This commit adds the ability to configure how a docvalue field should be
formatted, so that it would be possible eg. to return a date field
formatted as the number of milliseconds since Epoch.
Closes#27740
Currently the first snippet in the documentation test in script-fields.asciidoc
isn't executed, although it has the CONSOLE annotation. Adding a test setup
annotation to it seems to fix the problem.
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).
* Clarify documentation of scroll_id
The Scroll API may return the same scroll ID for multiple requests due to server side state. This is not clear from the current documentation.
* Further clarify scroll ID return behaviour