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Full-text queries

This page lists all full-text query types and common options. There are many optional fields that you can use to create subtle search behaviors, so we recommend that you test out some basic query types against representative indexes and verify the output before you perform more advanced or complex searches with multiple options.

OpenSearch uses the Apache Lucene search library, which provides highly efficient data structures and algorithms for ingesting, indexing, searching, and aggregating data.

To learn more about search query classes, see Lucene query JavaDocs.

The full-text query types shown in this section use the standard analyzer, which analyzes text automatically when the query is submitted.

Table of contents

  1. TOC {:toc}

Common terms queries and the optional query field cutoff_frequency are now deprecated. {: .note }

Query types

OpenSearch Query DSL provides multiple query types that you can use in your searches.

Match

Use the match query for full-text search of a specific document field. The match query analyzes the provided search string and returns documents that match any of the string's terms.

You can use Boolean query operators to combine searches.

The following example shows a basic match search for the title field set to the value wind:

GET _search
{
  "query": {
    "match": {
      "title": "wind"
    }
  }
}

For an example that uses curl, try:

curl --insecure -XGET -u 'admin:admin' https://<host>:<port>/<index>/_search \
  -H "content-type: application/json" \
  -d '{
    "query": {
      "match": {
        "title": "wind"
      }
    }
  }'

The query accepts the following options. For descriptions of each, see Advanced filter options.

GET _search
{
  "query": {
    "match": {
      "title": {
        "query": "wind",
        "fuzziness": "AUTO",
        "fuzzy_transpositions": true,
        "operator":  "or",
        "minimum_should_match": 1,
        "analyzer": "standard",
        "zero_terms_query": "none",
        "lenient": false,
        "prefix_length": 0,
        "max_expansions": 50,
        "boost": 1
      }
    }
  }
}

Multi-match

You can use the multi_match query type to search multiple fields. Multi-match operation functions similarly to the match operation.

The ^ lets you "boost" certain fields. Boosts are multipliers that weigh matches in one field more heavily than matches in other fields. In the following example, a match for "wind" in the title field influences _score four times as much as a match in the plot field. The result is that films like The Wind Rises and Gone with the Wind are near the top of the search results, and films like Twister and Sharknado, which presumably have "wind" in their plot summaries, are near the bottom.

GET _search
{
  "query": {
    "multi_match": {
      "query": "wind",
      "fields": ["title^4", "plot"]
    }
  }
}

The query accepts the following options. For descriptions of each, see Advanced filter options.

GET _search
{
  "query": {
    "multi_match": {
      "query": "wind",
      "fields": ["title^4", "description"],
      "type": "most_fields",
      "operator": "and",
      "minimum_should_match": 3,
      "tie_breaker": 0.0,
      "analyzer": "standard",
      "boost": 1,
      "fuzziness": "AUTO",
      "fuzzy_transpositions": true,
      "lenient": false,
      "prefix_length": 0,
      "max_expansions": 50,
      "auto_generate_synonyms_phrase_query": true,
      "zero_terms_query": "none"
    }
  }
}

Match Boolean prefix

The match_bool_prefix query analyzes the provided search string and creates a bool query from the string's terms. It uses every term except the last term as a whole word for matching. The last term is used as a prefix. The match_bool_prefix query returns documents that contain either the whole-word terms or terms that start with the prefix term, in any order.

GET _search
{
  "query": {
    "match_bool_prefix": {
      "title": "rises wi"
    }
  }
}

The query accepts the following options. For descriptions of each, see Advanced filter options.

GET _search
{
  "query": {
    "match_bool_prefix": {
      "title": {
        "query": "rises wi",
        "fuzziness": "AUTO",
        "fuzzy_transpositions": true,
        "max_expansions": 50,
        "prefix_length": 0,
        "operator":  "or",
        "minimum_should_match": 2,
        "analyzer": "standard"
      }
    }
  }
}

For more reference information about prefix queries, see the Lucene documentation.

Match phrase

Use the match_phrase query to match documents that contain an exact phrase in a specified order. You can add flexibility to phrase matching by providing the slop parameter.

Creates a phrase query that matches a sequence of terms.

GET _search
{
  "query": {
    "match_phrase": {
      "title": "the wind rises"
    }
  }
}

The query accepts the following options. For descriptions of each, see Advanced filter options.

GET _search
{
  "query": {
    "match_phrase": {
      "title": {
        "query": "wind rises the",
        "slop": 3,
        "analyzer": "standard",
        "zero_terms_query": "none"
      }
    }
  }
}

Match phrase prefix

Use the match_phrase_prefix query to specify a phrase to match in order. The documents that contain the phrase you specify will be returned. The last partial term in the phrase is interpreted as a prefix, so any documents that contain phrases that begin with the phrase and prefix of the last term will be returned.

Similar to match phrase, but creates a prefix query out of the last term in the query string.

GET _search
{
  "query": {
    "match_phrase_prefix": {
      "title": "the wind ri"
    }
  }
}

The query accepts the following options. For descriptions of each, see Advanced filter options.

GET _search
{
  "query": {
    "match_phrase_prefix": {
      "title": {
        "query": "the wind ri",
        "analyzer": "standard",
        "max_expansions": 50,
        "slop": 3
      }
    }
  }
}

Query string

The query string query splits text based on operators and analyzes each individually.

If you search using the HTTP request parameters (i.e. _search?q=wind), OpenSearch creates a query string query. {: .note }

GET _search
{
  "query": {
    "query_string": {
      "query": "the wind AND (rises OR rising)"
    }
  }
}

The query accepts the following options. For descriptions of each, see Advanced filter options.

GET _search
{
  "query": {
    "query_string": {
      "query": "the wind AND (rises OR rising)",
      "default_field": "title",
      "type": "best_fields",
      "fuzziness": "AUTO",
      "fuzzy_transpositions": true,
      "fuzzy_max_expansions": 50,
      "fuzzy_prefix_length": 0,
      "minimum_should_match": 1,
      "default_operator": "or",
      "analyzer": "standard",
      "lenient": false,
      "boost": 1,
      "allow_leading_wildcard": true,
      "enable_position_increments": true,
      "phrase_slop": 3,
      "max_determinized_states": 10000,
      "time_zone": "-08:00",
      "quote_field_suffix": "",
      "quote_analyzer": "standard",
      "analyze_wildcard": false,
      "auto_generate_synonyms_phrase_query": true
    }
  }
}

Simple query string

Use the simple_query_string type to specify directly in the query string multiple arguments delineated by regular expressions. Searches with this type will discard any invalid portions of the string.

GET _search
{
  "query": {
    "simple_query_string": {
      "query": "\"rises wind the\"~4 | *ising~2",
      "fields": ["title"]
    }
  }
}
Special character Behavior
+ Acts as the and operator.
` `
* Acts as a wildcard.
"" Wraps several terms into a phrase.
() Wraps a clause for precedence.
~n When used after a term (for example, wnid~3), sets fuzziness. When used after a phrase, sets slop. Advanced filter options.
- Negates the term.

The query accepts the following options. For descriptions of each, see Advanced filter options.

GET _search
{
  "query": {
    "simple_query_string": {
      "query": "\"rises wind the\"~4 | *ising~2",
      "fields": ["title"],
      "flags": "ALL",
      "fuzzy_transpositions": true,
      "fuzzy_max_expansions": 50,
      "fuzzy_prefix_length": 0,
      "minimum_should_match": 1,
      "default_operator": "or",
      "analyzer": "standard",
      "lenient": false,
      "quote_field_suffix": "",
      "analyze_wildcard": false,
      "auto_generate_synonyms_phrase_query": true
    }
  }
}

Match all

The match_all query type will return all documents. This type can be useful in testing large document sets if you need to return the entire set.

GET _search
{
  "query": {
    "match_all": {}
  }
}

Advanced filter options

You can filter your query results by using some of the optional query fields, such as wildcards, fuzzy query fields, or synonyms. You can also use analyzers as optional query fields.

Wildcard options

Option Valid values Description
allow_leading_wildcard Boolean Whether * and ? are allowed as the first character of a search term. The default is true.
analyze_wildcard Boolean Whether OpenSearch should attempt to analyze wildcard terms. Some analyzers do a poor job at this task, so the default is false.

Fuzzy query options

Option Valid values Description
fuzziness AUTO, 0, or a positive integer The number of character edits (insert, delete, substitute) that it takes to change one word to another when determining whether a term matched a value. For example, the distance between wined and wind is 1. The default, AUTO, chooses a value based on the length of each term and is a good choice for most use cases.
fuzzy_transpositions Boolean Setting fuzzy_transpositions to true (default) adds swaps of adjacent characters to the insert, delete, and substitute operations of the fuzziness option. For example, the distance between wind and wnid is 1 if fuzzy_transpositions is true (swap "n" and "i") and 2 if it is false (delete "n", insert "n"). If fuzzy_transpositions is false, rewind and wnid have the same distance (2) from wind, despite the more human-centric opinion that wnid is an obvious typo. The default is a good choice for most use cases.
fuzzy_max_expansions Positive integer Fuzzy queries "expand to" a number of matching terms that are within the distance specified in fuzziness. Then OpenSearch tries to match those terms against its indexes.

Synonyms in a multiple terms search

You can also use synonyms with the terms query type to search for multiple terms. Use the auto_generate_synonyms_phrase_query Boolean field. By default it is set to true. It automatically generates phrase queries for multiple term synonyms. For example, if you have the synonym "ba, batting average" and search for "ba," OpenSearch searches for ba OR "batting average" when the option is true or ba OR (batting AND average) when the option is false.

To learn more about the multiple terms query type, see Terms. For more reference information about phrase queries, see the Lucene documentation.

Other advanced options

You can also use the following optional query fields to filter your query results.

Option Valid values Description
boost Floating-point Boosts the clause by the given multiplier. Useful for weighing clauses in compound queries. The default is 1.0.
enable_position_increments Boolean When true, result queries are aware of position increments. This setting is useful when the removal of stop words leaves an unwanted "gap" between terms. The default is true.
fields String array The list of fields to search (e.g. "fields": ["title^4", "description"]). If unspecified, defaults to the index.query.default_field setting, which defaults to ["*"].
flags String A `
lenient Boolean Setting lenient to true lets you ignore data type mismatches between the query and the document field. For example, a query string of "8.2" could match a field of type float. The default is false.
low_freq_operator and, or The operator for low-frequency terms. The default is or. See also operator in this table.
max_determinized_states Positive integer The maximum number of "states" (a measure of complexity) that Lucene can create for query strings that contain regular expressions (e.g. "query": "/wind.+?/"). Larger numbers allow for queries that use more memory. The default is 10,000.
max_expansions Positive integer max_expansions specifies the maximum number of terms to which the query can expand. The default is 50.
minimum_should_match Positive or negative integer, positive or negative percentage, combination If the query string contains multiple search terms and you used the or operator, the number of terms that need to match for the document to be considered a match. For example, if minimum_should_match is 2, "wind often rising" does not match "The Wind Rises." If minimum_should_match is 1, it matches.
operator or, and If the query string contains multiple search terms, whether all terms need to match (and) or only one term needs to match (or) for a document to be considered a match.
phrase_slop 0 (default) or a positive integer See slop.
prefix_length 0 (default) or a positive integer The number of leading characters that are not considered in fuzziness.
quote_field_suffix String This option lets you search different fields depending on whether terms are wrapped in quotes. For example, if quote_field_suffix is ".exact" and you search for "lightly" (in quotes) in the title field, OpenSearch searches the title.exact field. This second field might use a different type (e.g. keyword rather than text) or a different analyzer. The default is null.
rewrite constant_score, scoring_boolean, constant_score_boolean, top_terms_N, top_terms_boost_N, top_terms_blended_freqs_N Determines how OpenSearch rewrites and scores multi-term queries. The default is constant_score.
slop 0 (default) or a positive integer Controls the degree to which words in a query can be misordered and still be considered a match. From the Lucene documentation: "The number of other words permitted between words in query phrase. For example, to switch the order of two words requires two moves (the first move places the words atop one another), so to permit re-orderings of phrases, the slop must be at least two. A value of zero requires an exact match."
tie_breaker 0.0 (default) to 1.0 Changes the way OpenSearch scores searches. For example, a type of best_fields typically uses the highest score from any one field. If you specify a tie_breaker value between 0.0 and 1.0, the score changes to highest score + tie_breaker * score for all other matching fields. If you specify a value of 1.0, OpenSearch adds together the scores for all matching fields (effectively defeating the purpose of best_fields).
time_zone UTC offset hours Specifies the number of hours to offset the desired time zone from UTC. You need to indicate the time zone offset number if the query string contains a date range. For example, set time_zone": "-08:00" for a query with a date range such as "query": "wind rises release_date[2012-01-01 TO 2014-01-01]"). The default time zone format used to specify number of offset hours is UTC.
type best_fields, most_fields, cross_fields, phrase, phrase_prefix Determines how OpenSearch executes the query and scores the results. The default is best_fields.
zero_terms_query none, all If the analyzer removes all terms from a query string, whether to match no documents (default) or all documents. For example, the stop analyzer removes all terms from the string "an but this."