Query string query

You can specify fields to search in the query syntax:

Wildcard searches can be run on individual terms, using ? to replace a single character, and * to replace zero or more characters:

qu?ck bro*

Be aware that wildcard queries can use an enormous amount of memory and perform very badly — just think how many terms need to be queried to match the query string "a* b* c*".

{
  "field": ""
}

{
  "field": null
}

Only parts of the analysis chain that operate at the character level are applied. So for instance, if the analyzer performs both lowercasing and stemming, only the lowercasing will be applied: it would be wrong to perform stemming on a word that is missing some of its letters.

By setting analyze_wildcard to true, queries that end with a * will be analyzed and a boolean query will be built out of the different tokens, by ensuring exact matches on the first N-1 tokens, and prefix match on the last token.

Regular expression patterns can be embedded in the query string by wrapping them in forward-slashes ("/"):

name:/joh?n(ath[oa]n)/

The supported regular expression syntax is explained in Regular expression syntax.

/.*n/

You can run fuzzy queries using the ~ operator:

quikc~ brwn~ foks~

For these queries, the query string is normalized. If present, only certain filters from the analyzer are applied. For a list of applicable filters, see Normalizers.

The query uses the Damerau-Levenshtein distance to find all terms with a maximum of two changes, where a change is the insertion, deletion or substitution of a single character, or transposition of two adjacent characters.

The default edit distance is 2, but an edit distance of 1 should be sufficient to catch 80% of all human misspellings. It can be specified as:

quikc~1

While a phrase query (eg "john smith") expects all of the terms in exactly the same order, a proximity query allows the specified words to be further apart or in a different order. In the same way that fuzzy queries can specify a maximum edit distance for characters in a word, a proximity search allows us to specify a maximum edit distance of words in a phrase:

"fox quick"~5

The closer the text in a field is to the original order specified in the query string, the more relevant that document is considered to be. When compared to the above example query, the phrase "quick fox" would be considered more relevant than "quick brown fox".

Ranges can be specified for date, numeric or string fields. Inclusive ranges are specified with square brackets [min TO max] and exclusive ranges with curly brackets {min TO max}.

Curly and square brackets can be combined:

Ranges with one side unbounded can use the following syntax:

age:>10
age:>=10
age:<10
age:<=10

age:(>=10 AND <20)
age:(+>=10 +<20)

The parsing of ranges in query strings can be complex and error prone. It is much more reliable to use an explicit range query.

Use the boost operator ^ to make one term more relevant than another. For instance, if we want to find all documents about foxes, but we are especially interested in quick foxes:

quick^2 fox

The default boost value is 1, but can be any positive floating point number. Boosts between 0 and 1 reduce relevance.

Boosts can also be applied to phrases or to groups:

"john smith"^2   (foo bar)^4

By default, all terms are optional, as long as one term matches. A search for foo bar baz will find any document that contains one or more of foo or bar or baz. We have already discussed the default_operator above which allows you to force all terms to be required, but there are also boolean operators which can be used in the query string itself to provide more control.

The preferred operators are + (this term must be present) and - (this term must not be present). All other terms are optional. For example, this query:

quick brown +fox -news

states that:

The familiar boolean operators AND, OR and NOT (also written &&, || and !) are also supported but beware that they do not honor the usual precedence rules, so parentheses should be used whenever multiple operators are used together. For instance the previous query could be rewritten as:

In contrast, the same query rewritten using the match query would look like this:

{
    "bool": {
        "must":     { "match": "fox"         },
        "should":   { "match": "quick brown" },
        "must_not": { "match": "news"        }
    }
}

Multiple terms or clauses can be grouped together with parentheses, to form sub-queries:

(quick OR brown) AND fox

Groups can be used to target a particular field, or to boost the result of a sub-query:

status:(active OR pending) title:(full text search)^2

If you need to use any of the characters which function as operators in your query itself (and not as operators), then you should escape them with a leading backslash. For instance, to search for (1+1)=2, you would need to write your query as \(1\+1\)\=2. When using JSON for the request body, two preceding backslashes (\\) are required; the backslash is a reserved escaping character in JSON strings.

response = client.search(
  index: 'my-index-000001',
  body: {
    query: {
      query_string: {
        query: 'kimchy\\!',
        fields: [
          'user.id'
        ]
      }
    }
  }
)
puts response

GET /my-index-000001/_search
{
  "query" : {
    "query_string" : {
      "query" : "kimchy\\!",
      "fields"  : ["user.id"]
    }
  }
}

The reserved characters are: + - = && || > < ! ( ) { } [ ] ^ " ~ * ? : \ /

Failing to escape these special characters correctly could lead to a syntax error which prevents your query from running.

Whitespace is not considered an operator.

If the query string is empty or only contains whitespaces the query will yield an empty result set.

query_string searches do not return nested documents. To search nested documents, use the nested query.

You can use the fields parameter to perform a query_string search across multiple fields.

The idea of running the query_string query against multiple fields is to expand each query term to an OR clause like this:

field1:query_term OR field2:query_term | ...

For example, the following query

response = client.search(
  body: {
    query: {
      query_string: {
        fields: [
          'content',
          'name'
        ],
        query: 'this AND that'
      }
    }
  }
)
puts response

res, err := es.Search(
	es.Search.WithBody(strings.NewReader(`{
	  "query": {
	    "query_string": {
	      "fields": [
	        "content",
	        "name"
	      ],
	      "query": "this AND that"
	    }
	  }
	}`)),
	es.Search.WithPretty(),
)
fmt.Println(res, err)

GET /_search
{
  "query": {
    "query_string": {
      "fields": [ "content", "name" ],
      "query": "this AND that"
    }
  }
}

matches the same words as

response = client.search(
  body: {
    query: {
      query_string: {
        query: '(content:this OR name:this) AND (content:that OR name:that)'
      }
    }
  }
)
puts response

res, err := es.Search(
	es.Search.WithBody(strings.NewReader(`{
	  "query": {
	    "query_string": {
	      "query": "(content:this OR name:this) AND (content:that OR name:that)"
	    }
	  }
	}`)),
	es.Search.WithPretty(),
)
fmt.Println(res, err)

GET /_search
{
  "query": {
    "query_string": {
      "query": "(content:this OR name:this) AND (content:that OR name:that)"
    }
  }
}

Since several queries are generated from the individual search terms, combining them is automatically done using a dis_max query with a tie_breaker. For example (the name is boosted by 5 using ^5 notation):

response = client.search(
  body: {
    query: {
      query_string: {
        fields: [
          'content',
          'name^5'
        ],
        query: 'this AND that OR thus',
        tie_breaker: 0
      }
    }
  }
)
puts response

res, err := es.Search(
	es.Search.WithBody(strings.NewReader(`{
	  "query": {
	    "query_string": {
	      "fields": [
	        "content",
	        "name^5"
	      ],
	      "query": "this AND that OR thus",
	      "tie_breaker": 0
	    }
	  }
	}`)),
	es.Search.WithPretty(),
)
fmt.Println(res, err)

GET /_search
{
  "query": {
    "query_string" : {
      "fields" : ["content", "name^5"],
      "query" : "this AND that OR thus",
      "tie_breaker" : 0
    }
  }
}

Simple wildcard can also be used to search "within" specific inner elements of the document. For example, if we have a city object with several fields (or inner object with fields) in it, we can automatically search on all "city" fields:

response = client.search(
  body: {
    query: {
      query_string: {
        fields: [
          'city.*'
        ],
        query: 'this AND that OR thus'
      }
    }
  }
)
puts response

res, err := es.Search(
	es.Search.WithBody(strings.NewReader(`{
	  "query": {
	    "query_string": {
	      "fields": [
	        "city.*"
	      ],
	      "query": "this AND that OR thus"
	    }
	  }
	}`)),
	es.Search.WithPretty(),
)
fmt.Println(res, err)

GET /_search
{
  "query": {
    "query_string" : {
      "fields" : ["city.*"],
      "query" : "this AND that OR thus"
    }
  }
}

Another option is to provide the wildcard fields search in the query string itself (properly escaping the * sign), for example: city.\*:something:

response = client.search(
  body: {
    query: {
      query_string: {
        query: 'city.\\*:(this AND that OR thus)'
      }
    }
  }
)
puts response

res, err := es.Search(
	es.Search.WithBody(strings.NewReader(`{
	  "query": {
	    "query_string": {
	      "query": "city.\\*:(this AND that OR thus)"
	    }
	  }
	}`)),
	es.Search.WithPretty(),
)
fmt.Println(res, err)

GET /_search
{
  "query": {
    "query_string" : {
      "query" : "city.\\*:(this AND that OR thus)"
    }
  }
}

The fields parameter can also include pattern based field names, allowing to automatically expand to the relevant fields (dynamically introduced fields included). For example:

response = client.search(
  body: {
    query: {
      query_string: {
        fields: [
          'content',
          'name.*^5'
        ],
        query: 'this AND that OR thus'
      }
    }
  }
)
puts response

res, err := es.Search(
	es.Search.WithBody(strings.NewReader(`{
	  "query": {
	    "query_string": {
	      "fields": [
	        "content",
	        "name.*^5"
	      ],
	      "query": "this AND that OR thus"
	    }
	  }
	}`)),
	es.Search.WithPretty(),
)
fmt.Println(res, err)

GET /_search
{
  "query": {
    "query_string" : {
      "fields" : ["content", "name.*^5"],
      "query" : "this AND that OR thus"
    }
  }
}

When running the query_string query against multiple fields, the following additional parameters are supported.