---
layout: default
title: Bulk
parent: REST API reference
nav_order: 5
---

# Bulk

The bulk operation lets you add, update, or delete many documents in a single request. Compared to individual OpenSearch indexing requests, the bulk operation has significant performance benefits. Whenever practical, we recommend batching indexing operations into bulk requests.


## Example

```json
POST _bulk
{ "delete": { "_index": "movies", "_id": "tt2229499" } }
{ "index": { "_index": "movies", "_id": "tt1979320" } }
{ "title": "Rush", "year": 2013 }
{ "create": { "_index": "movies", "_id": "tt1392214" } }
{ "title": "Prisoners", "year": 2013 }
{ "update": { "_index": "movies", "_id": "tt0816711" } }
{ "doc" : { "title": "World War Z" } }

```


## Path and HTTP methods

```
POST _bulk
POST {index}/_bulk
```

Specifying the index in the path means you don't need to include it in the [request body](#request-body).

OpenSearch also accepts PUT requests to the `_bulk` path, but we highly recommend using POST. The accepted usage of PUT---adding or replacing a single resource at a given path---doesn't make sense for bulk requests.
{: .note }


## URL parameters

All bulk URL parameters are optional.

Parameter | Type | Description
:--- | :--- | :---
pipeline | String | The pipeline ID for preprocessing documents.
refresh | Enum | Whether to refresh the affected shards after performing the indexing operations. Default is `false`. `true` makes the changes show up in search results immediately, but hurts cluster performance. `wait_for` waits for a refresh. Requests take longer to return, but cluster performance doesn't suffer.
require_alias | Boolean | Set to `true` to require that all actions target an index alias rather than an index. Default is `false`.
routing | String | Routes the request to the specified shard.
timeout | Time | How long to wait for the request to return. Default `1m`.
type | String | (Deprecated) The default document type for documents that don't specify a type. Default is `_doc`. We highly recommend ignoring this parameter and using a type of `_doc` for all indices.
wait_for_active_shards | String | Specifies the number of active shards that must be available before OpenSearch processes the bulk request. Default is 1 (only the primary shard). Set to `all` or a positive integer. Values greater than 1 require replicas. For example, if you specify a value of 3, the index must have two replicas distributed across two additional nodes for the request to succeed.
{% comment %}_source | List | asdf
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## Request body

The bulk request body follows this pattern:

```
Action and metadata\n
Optional document\n
Action and metadata\n
Optional document\n

```

The optional JSON document doesn't need to be minified---spaces are fine---but it does need to be on a single line. OpenSearch uses newline characters to parse bulk requests and requires that the request body end with a newline character.

All actions support the same metadata: `_index`, `_id`, and `_require_alias`. If you don't provide an ID, OpenSearch generates one automatically, which can make it challenging to update the document at a later time.

- Create

  Creates a document if it doesn't already exist and returns an error otherwise. The next line must include a JSON document.

  ```json
  { "create": { "_index": "movies", "_id": "tt1392214" } }
  { "title": "Prisoners", "year": 2013 }
  ```

- Delete

  This action deletes a document if it exists. If the document doesn't exist, OpenSearch doesn't return an error, but instead returns `not_found` under `result`. Delete actions don't require documents on the next line.

  ```json
  { "delete": { "_index": "movies", "_id": "tt2229499" } }
  ```

- Index

  Index actions create a document if it doesn't yet exist and replace the document if it already exists. The next line must include a JSON document.

  ```json
  { "index": { "_index": "movies", "_id": "tt1979320" } }
  { "title": "Rush", "year": 2013}
  ```

- Update

  This action updates existing documents and returns an error if the document doesn't exist. The next line must include a full or partial JSON document, depending on how much of the document you want to update. It can also include a script or upsert for more complex document updates.

  ```json
  { "update": { "_index": "movies", "_id": "tt0816711" } }
  { "doc" : { "title": "World War Z" } }
  ```


## Response

In the response, pay particular attention to the top-level `errors` boolean. If true, you can iterate over the individual actions for more detailed information.

```json
{
  "took": 11,
  "errors": true,
  "items": [
    {
      "index": {
        "_index": "movies",
        "_type": "_doc",
        "_id": "tt1979320",
        "_version": 1,
        "result": "created",
        "_shards": {
          "total": 2,
          "successful": 1,
          "failed": 0
        },
        "_seq_no": 1,
        "_primary_term": 1,
        "status": 201
      }
    },
    {
      "create": {
        "_index": "movies",
        "_type": "_doc",
        "_id": "tt1392214",
        "status": 409,
        "error": {
          "type": "version_conflict_engine_exception",
          "reason": "[tt1392214]: version conflict, document already exists (current version [1])",
          "index": "movies",
          "shard": "0",
          "index_uuid": "yhizhusbSWmP0G7OJnmcLg"
        }
      }
    },
    {
      "update": {
        "_index": "movies",
        "_type": "_doc",
        "_id": "tt0816711",
        "status": 404,
        "error": {
          "type": "document_missing_exception",
          "reason": "[_doc][tt0816711]: document missing",
          "index": "movies",
          "shard": "0",
          "index_uuid": "yhizhusbSWmP0G7OJnmcLg"
        }
      }
    }
  ]
}
```