Exists query

Exists query

Returns documents that contain an indexed value for a field.

An indexed value may not exist for a document’s field due to a variety of reasons:

  • The field in the source JSON is null or []
  • The field has "index" : false set in the mapping
  • The length of the field value exceeded an ignore_above setting in the mapping
  • The field value was malformed and ignore_malformed was defined in the mapping

Example request

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

Top-level parameters for exists

field

(Required, string) Name of the field you wish to search.

While a field is deemed non-existent if the JSON value is null or [], these values will indicate the field does exist:

  • Empty strings, such as "" or "-"
  • Arrays containing null and another value, such as [null, "foo"]
  • A custom null-value, defined in field mapping

Notes

Find documents missing indexed values

To find documents that are missing an indexed value for a field, use the must_not boolean query with the exists query.

The following search returns documents that are missing an indexed value for the user.id field.

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