71 lines
1.8 KiB
Markdown
71 lines
1.8 KiB
Markdown
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---
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navigation_title: "Exists"
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mapped_pages:
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- https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-exists-query.html
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---
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# Exists query [query-dsl-exists-query]
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Returns documents that contain an indexed value for a field.
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An indexed value may not exist for a document’s field due to a variety of reasons:
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* The field in the source JSON is `null` or `[]`
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* The field has `"index" : false` and `"doc_values" : false` set in the mapping
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* The length of the field value exceeded an `ignore_above` setting in the mapping
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* The field value was malformed and `ignore_malformed` was defined in the mapping
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## Example request [exists-query-ex-request]
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```console
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GET /_search
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{
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"query": {
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"exists": {
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"field": "user"
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}
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}
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}
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```
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## Top-level parameters for `exists` [exists-query-top-level-params]
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`field`
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: (Required, string) Name of the field you wish to search.
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While a field is deemed non-existent if the JSON value is `null` or `[]`, these values will indicate the field does exist:
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* Empty strings, such as `""` or `"-"`
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* Arrays containing `null` and another value, such as `[null, "foo"]`
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* A custom [`null-value`](/reference/elasticsearch/mapping-reference/null-value.md), defined in field mapping
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## Notes [exists-query-notes]
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### Find documents missing indexed values [find-docs-null-values]
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To find documents that are missing an indexed value for a field, use the `must_not` [boolean query](/reference/query-languages/query-dsl/query-dsl-bool-query.md) with the `exists` query.
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The following search returns documents that are missing an indexed value for the `user.id` field.
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```console
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GET /_search
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{
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"query": {
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"bool": {
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"must_not": {
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"exists": {
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"field": "user.id"
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}
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}
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}
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}
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}
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```
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