---
title: "Update a dataset split"
method: PATCH
path: "/v1/datasets/{dataset_identifier}/splits/{split_id}"
tags: ["datasets"]
---

# Update a dataset split

`PATCH /v1/datasets/{dataset_identifier}/splits/{split_id}`

## Path parameters

- `dataset_identifier` string, required — The dataset identifier: either dataset ID or dataset name.
- `split_id` string, required — The ID (GlobalID) of the dataset split.

## Request body

- UpdateDatasetSplitRequestBody
  - `name` string, nullable — A new unique name for the split.
  - `description` string, nullable — A new description, or null to clear it.
  - `color` string, nullable — A new hex color for the split.
  - `metadata` object, nullable — New JSON metadata that replaces the existing metadata.
  - `add_example_ids` string[] — Dataset example IDs (GlobalIDs) to add to the split. Each example must belong to this dataset. Adding an example already in the split is a no-op.
  - `remove_example_ids` string[] — Dataset example IDs (GlobalIDs) to remove from the split.

## Response `200`

Successful Response

- UpdateDatasetSplitResponseBody
  - `data` DatasetSplit, required
    - `id` string, required
    - `name` string, required
    - `description` string, nullable, required
    - `color` string, required
    - `metadata` object, required
    - `example_count` integer, required
    - `created_at` string, date-time, required
    - `updated_at` string, date-time, required

## Other responses

- `403` — Forbidden
- `404` — Dataset, split, or example not found
- `409` — A dataset split with the given name already exists
- `422` — Invalid request

---

[API](https://skmtc.net/arize-ai/apis/arize-phoenix-rest-api.md) · [All operations](https://skmtc.net/arize-ai/apis/arize-phoenix-rest-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/arize-ai/arize-phoenix-rest-api/versions/a14d8ad6f708/schema)