Exists query

Use the exists query to search for documents that contain a specific field.

An indexed value will not exist for a document field in any of the following cases:

  • The field has "index" : false specified in the mapping.
  • The field in the source JSON is null or [].
  • The length of the field value exceeds the ignore_above setting in the mapping.
  • The field value is malformed and ignore_malformed is defined in the mapping.

An indexed value will exist for a document field in any of the following cases:

  • The value is an array that contains one or more null elements and one or more non-null elements (for example, ["one", null]).
  • The value is an empty string ("" or "-").
  • The value is a custom null_value, as defined in the field mapping.

Example

For example, consider an index that contains the following two documents:

  1. PUT testindex/_doc/1
  2. {
  3.   "title": "The wind rises"
  4. }

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  1. PUT testindex/_doc/2
  2. {
  3.   "title": "Gone with the wind",
  4.   "description": "A 1939 American epic historical film"
  5. }

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The following query searches for documents that contain the description field:

  1. GET testindex/_search
  2. {
  3.   "query": {
  4.     "exists": {
  5.       "field": "description"
  6.     }
  7.   }
  8. }

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The response contains the matching document:

  1. {
  2.   "took": 3,
  3.   "timed_out": false,
  4.   "_shards": {
  5.     "total": 1,
  6.     "successful": 1,
  7.     "skipped": 0,
  8.     "failed": 0
  9.   },
  10.   "hits": {
  11.     "total": {
  12.       "value": 1,
  13.       "relation": "eq"
  14.     },
  15.     "max_score": 1,
  16.     "hits": [
  17.       {
  18.         "_index": "testindex",
  19.         "_id": "2",
  20.         "_score": 1,
  21.         "_source": {
  22.           "title": "Gone with the wind",
  23.           "description": "A 1939 American epic historical film"
  24.         }
  25.       }
  26.     ]
  27.   }
  28. }

Finding documents with missing indexed values

To find documents with missing indexed values, you can use the must_not Boolean query with the inner exists query. For example, the following request searches for documents in which the description field is missing:

  1. GET testindex/_search
  2. {
  3.   "query": {
  4.     "bool": {
  5.       "must_not": {
  6.         "exists": {
  7.           "field": "description"
  8.         }
  9.       }
  10.     }
  11.   }
  12. }

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The response contains the matching document:

  1. {
  2.   "took": 19,
  3.   "timed_out": false,
  4.   "_shards": {
  5.     "total": 1,
  6.     "successful": 1,
  7.     "skipped": 0,
  8.     "failed": 0
  9.   },
  10.   "hits": {
  11.     "total": {
  12.       "value": 1,
  13.       "relation": "eq"
  14.     },
  15.     "max_score": 0,
  16.     "hits": [
  17.       {
  18.         "_index": "testindex",
  19.         "_id": "1",
  20.         "_score": 0,
  21.         "_source": {
  22.           "title": "The wind rises"
  23.         }
  24.       }
  25.     ]
  26.   }
  27. }

Parameters

The query accepts the name of the field (<field>) as a top-level parameter.