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- [[query-dsl-match-query]]
- === Match Query
- `match` queries accept text/numerics/dates, analyzes
- them, and constructs a query. For example:
- [source,js]
- --------------------------------------------------
- GET /_search
- {
- "query": {
- "match" : {
- "message" : "this is a test"
- }
- }
- }
- --------------------------------------------------
- // CONSOLE
- Note, `message` is the name of a field, you can substitute the name of
- any field instead.
- [[query-dsl-match-query-boolean]]
- ==== match
- The `match` query is of type `boolean`. It means that the text
- provided is analyzed and the analysis process constructs a boolean query
- from the provided text. The `operator` flag can be set to `or` or `and`
- to control the boolean clauses (defaults to `or`). The minimum number of
- optional `should` clauses to match can be set using the
- <<query-dsl-minimum-should-match,`minimum_should_match`>>
- parameter.
- The `analyzer` can be set to control which analyzer will perform the
- analysis process on the text. It defaults to the field explicit mapping
- definition, or the default search analyzer.
- The `lenient` parameter can be set to `true` to ignore exceptions caused by
- data-type mismatches, such as trying to query a numeric field with a text
- query string. Defaults to `false`.
- [[query-dsl-match-query-fuzziness]]
- ===== Fuzziness
- `fuzziness` allows _fuzzy matching_ based on the type of field being queried.
- See <<fuzziness>> for allowed settings.
- The `prefix_length` and
- `max_expansions` can be set in this case to control the fuzzy process.
- If the fuzzy option is set the query will use `top_terms_blended_freqs_${max_expansions}`
- as its <<query-dsl-multi-term-rewrite,rewrite
- method>> the `fuzzy_rewrite` parameter allows to control how the query will get
- rewritten.
- Fuzzy transpositions (`ab` -> `ba`) are allowed by default but can be disabled
- by setting `fuzzy_transpositions` to `false`.
- Here is an example when providing additional parameters (note the slight
- change in structure, `message` is the field name):
- [source,js]
- --------------------------------------------------
- GET /_search
- {
- "query": {
- "match" : {
- "message" : {
- "query" : "this is a test",
- "operator" : "and"
- }
- }
- }
- }
- --------------------------------------------------
- // CONSOLE
- [[query-dsl-match-query-zero]]
- ===== Zero terms query
- If the analyzer used removes all tokens in a query like a `stop` filter
- does, the default behavior is to match no documents at all. In order to
- change that the `zero_terms_query` option can be used, which accepts
- `none` (default) and `all` which corresponds to a `match_all` query.
- [source,js]
- --------------------------------------------------
- GET /_search
- {
- "query": {
- "match" : {
- "message" : {
- "query" : "to be or not to be",
- "operator" : "and",
- "zero_terms_query": "all"
- }
- }
- }
- }
- --------------------------------------------------
- // CONSOLE
- [[query-dsl-match-query-cutoff]]
- ===== Cutoff frequency
- The match query supports a `cutoff_frequency` that allows
- specifying an absolute or relative document frequency where high
- frequency terms are moved into an optional subquery and are only scored
- if one of the low frequency (below the cutoff) terms in the case of an
- `or` operator or all of the low frequency terms in the case of an `and`
- operator match.
- This query allows handling `stopwords` dynamically at runtime, is domain
- independent and doesn't require a stopword file. It prevents scoring /
- iterating high frequency terms and only takes the terms into account if a
- more significant / lower frequency term matches a document. Yet, if all
- of the query terms are above the given `cutoff_frequency` the query is
- automatically transformed into a pure conjunction (`and`) query to
- ensure fast execution.
- The `cutoff_frequency` can either be relative to the total number of
- documents if in the range `[0..1)` or absolute if greater or equal to
- `1.0`.
- Here is an example showing a query composed of stopwords exclusively:
- [source,js]
- --------------------------------------------------
- GET /_search
- {
- "query": {
- "match" : {
- "message" : {
- "query" : "to be or not to be",
- "cutoff_frequency" : 0.001
- }
- }
- }
- }
- --------------------------------------------------
- // CONSOLE
- IMPORTANT: The `cutoff_frequency` option operates on a per-shard-level. This means
- that when trying it out on test indexes with low document numbers you
- should follow the advice in {defguide}/relevance-is-broken.html[Relevance is broken].
- [[query-dsl-match-query-synonyms]]
- ===== Synonyms
- The `match` query supports multi-terms synonym expansion with the <<analysis-synonym-graph-tokenfilter,
- synonym_graph>> token filter. When this filter is used, the parser creates a phrase query for each multi-terms synonyms.
- For example, the following synonym: `"ny, new york" would produce:`
- `(ny OR ("new york"))`
- It is also possible to match multi terms synonyms with conjunctions instead:
- [source,js]
- --------------------------------------------------
- GET /_search
- {
- "query": {
- "match" : {
- "message": {
- "query" : "ny city",
- "auto_generate_synonyms_phrase_query" : false
- }
- }
- }
- }
- --------------------------------------------------
- // CONSOLE
- The example above creates a boolean query:
- `(ny OR (new AND york)) city)`
- that matches documents with the term `ny` or the conjunction `new AND york`.
- By default the parameter `auto_generate_synonyms_phrase_query` is set to `true`.
- .Comparison to query_string / field
- **************************************************
- The match family of queries does not go through a "query parsing"
- process. It does not support field name prefixes, wildcard characters,
- or other "advanced" features. For this reason, chances of it failing are
- very small / non existent, and it provides an excellent behavior when it
- comes to just analyze and run that text as a query behavior (which is
- usually what a text search box does). Also, the <<query-dsl-match-query-phrase-prefix,`match_phrase_prefix`>>
- type can provide a great "as you type" behavior to automatically load search results.
- **************************************************
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