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Multi-get documents

Introduced 1.0 {: .label .label-purple }

The multi-get operation allows you to execute multiple GET operations in one request, so you can get back all documents that match your criteria.

Example without specifying index in URL

GET _mget

{
  "docs": [
  {
    "_index": "sample-index1",
    "_id": "1"
  },
  {
    "_index": "sample-index2",
    "_id": "1",
    "_source": {
      "include": ["Length"]
    }
  }
  ]
}

Example of specifying index in URL

GET sample-index1/_mget

{
  "docs": [
    {
      "_type": "_doc",
      "_id": "1",
      "_source": false
    },
    {
      "_type": "_doc",
      "_id": "2",
      "_source": [ "Director", "Title" ]
    }
  ]
}

Path and HTTP methods

GET _mget
GET <index>/_mget

URL parameters

All multi-get URL parameters are optional.

Parameter Type Description
<index> String Name of the index to retrieve documents from.
preference String The node or shard that OpenSearch should perform the operation on. Default is random.
realtime Boolean Specifies whether the operation should run in realtime. If false, the operation waits for the index to refresh to analyze the source to retrieve data, which makes the operation near-realtime. Default is true.
refresh Boolean If true, OpenSearch refreshes shards to make the operation visible to searching. Default is false.
routing String A value used to route the operation to a specific shard.
stored_fields Boolean If true, the operation retrieves document fields stored in the index rather than the document's _source. Default is false.
_source String Whether to include the _source field in the query response. Default is true.
_source_excludes String A comma-separated list of source fields to exclude in the query response.
_source_includes String A comma-separated list of source fields to include in the query response.

Request body

If you don't specify an index in your request's URL, you must specify your target indices and the relevant document IDs in the request body. Other fields are optional.

Field Type Description Required
docs Array The documents you want to retrieve data from. Can contain the attributes: _id, _index, _routing, _source, and _stored_fields. If you specify an index in the URL, you can omit this field and add IDs of the documents to retrieve. Yes if an index is not specified in the URL
_id String The ID of the document. Yes if docs is specified in the request body
_index String Name of the index. Yes if an index is not specified in the URL
_routing String The value of the shard that has the document. Yes if a routing value was used when indexing the document
_source Object Specifies whether to return the _source field from an index (boolean), whether to return specific fields (array), or whether to include or exclude certain fields. No
_source.includes Array Specifies which fields to include in the query response. For example, "_source": { "include": ["Title"] } retrieves Title from the index. No
_source.excludes Array Specifies which fields to exclude in the query response. For example, "_source": { "exclude": ["Director"] } excludes Director from the query response. No
ids Array IDs of the documents to retrieve. Only allowed when an index is specified in the URL. No

Response

{
  "docs": [
    {
      "_index": "sample-index1",
      "_type": "_doc",
      "_id": "1",
      "_version": 4,
      "_seq_no": 5,
      "_primary_term": 19,
      "found": true,
      "_source": {
        "Title": "Batman Begins",
        "Director": "Christopher Nolan"
      }
    },
    {
      "_index": "sample-index2",
      "_type": "_doc",
      "_id": "1",
      "_version": 1,
      "_seq_no": 6,
      "_primary_term": 19,
      "found": true,
      "_source": {
        "Title": "The Dark Knight",
        "Director": "Christopher Nolan"
      }
    }
  ]
}

Response body fields

Field Description
_index The name of the index.
_type The document's type. OpenSearch only supports one type, which is _doc.
_id The document's ID.
_version The document's version number. Updated whenever the document changes.
_seq_no The sequnce number assigned when the document is indexed.
primary_term The primary term assigned when the document is indexed.
found Whether the document exists.
_routing The shard that the document is routed to. If the document is not routed to a particular shard, this field is omitted.
_source Contains the document's data if found is true. If _source is set to false or stored_fields is set to true in the URL parameters, this field is omitted.
_fields Contains the document's data that's stored in the index. Only returned if both stored_fields and found are true.