_id field

_id field

Each document has an _id that uniquely identifies it, which is indexed so that documents can be looked up either with the GET API or the ids query. The _id can either be assigned at indexing time, or a unique _id can be generated by Elasticsearch. This field is not configurable in the mappings.

The value of the _id field is accessible in queries such as term, terms, match, and query_string.

  1. resp = client.index(
  2.     index="my-index-000001",
  3.     id="1",
  4.     document={
  5.         "text": "Document with ID 1"
  6.     },
  7. )
  8. print(resp)
  10. resp1 = client.index(
  11.     index="my-index-000001",
  12.     id="2",
  13.     refresh=True,
  14.     document={
  15.         "text": "Document with ID 2"
  16.     },
  17. )
  18. print(resp1)
  20. resp2 = client.search(
  21.     index="my-index-000001",
  22.     query={
  23.         "terms": {
  24.             "_id": [
  25.                 "1",
  26.                 "2"
  27.             ]
  28.         }
  29.     },
  30. )
  31. print(resp2)
  1. response = client.index(
  2.   index: 'my-index-000001',
  3.   id: 1,
  4.   body: {
  5.     text: 'Document with ID 1'
  6.   }
  7. )
  8. puts response
  10. response = client.index(
  11.   index: 'my-index-000001',
  12.   id: 2,
  13.   refresh: true,
  14.   body: {
  15.     text: 'Document with ID 2'
  16.   }
  17. )
  18. puts response
  20. response = client.search(
  21.   index: 'my-index-000001',
  22.   body: {
  23.     query: {
  24.       terms: {
  25.         _id: [
  26.           '1',
  27.           '2'
  28.         ]
  29.       }
  30.     }
  31.   }
  32. )
  33. puts response
  1. {
  2.     res, err := es.Index(
  3.         "my-index-000001",
  4.         strings.NewReader(`{
  5.       "text": "Document with ID 1"
  6.     }`),
  7.         es.Index.WithDocumentID("1"),
  8.         es.Index.WithPretty(),
  9.     )
  10.     fmt.Println(res, err)
  11. }
  13. {
  14.     res, err := es.Index(
  15.         "my-index-000001",
  16.         strings.NewReader(`{
  17.       "text": "Document with ID 2"
  18.     }`),
  19.         es.Index.WithDocumentID("2"),
  20.         es.Index.WithRefresh("true"),
  21.         es.Index.WithPretty(),
  22.     )
  23.     fmt.Println(res, err)
  24. }
  26. {
  27.     res, err := es.Search(
  28.         es.Search.WithIndex("my-index-000001"),
  29.         es.Search.WithBody(strings.NewReader(`{
  30.       "query": {
  31.         "terms": {
  32.           "_id": [
  33.             "1",
  34.             "2"
  35.           ]
  36.         }
  37.       }
  38.     }`)),
  39.         es.Search.WithPretty(),
  40.     )
  41.     fmt.Println(res, err)
  42. }
  1. const response = await client.index({
  2.   index: "my-index-000001",
  3.   id: 1,
  4.   document: {
  5.     text: "Document with ID 1",
  6.   },
  7. });
  8. console.log(response);
  10. const response1 = await client.index({
  11.   index: "my-index-000001",
  12.   id: 2,
  13.   refresh: "true",
  14.   document: {
  15.     text: "Document with ID 2",
  16.   },
  17. });
  18. console.log(response1);
  20. const response2 = await client.search({
  21.   index: "my-index-000001",
  22.   query: {
  23.     terms: {
  24.       _id: ["1", "2"],
  25.     },
  26.   },
  27. });
  28. console.log(response2);
  1. # Example documents
  2. PUT my-index-000001/_doc/1
  3. {
  4.   "text": "Document with ID 1"
  5. }
  7. PUT my-index-000001/_doc/2?refresh=true
  8. {
  9.   "text": "Document with ID 2"
  10. }
  12. GET my-index-000001/_search
  13. {
  14.   "query": {
  15.     "terms": {
  16.       "_id": [ "1", "2" ] 
  17.     }
  18.   }
  19. }

Querying on the _id field (also see the ids query)

The _id field is restricted from use in aggregations, sorting, and scripting. In case sorting or aggregating on the _id field is required, it is advised to duplicate the content of the _id field into another field that has doc_values enabled.

_id is limited to 512 bytes in size and larger values will be rejected.