---
title: "Merge Datasets"
method: POST
path: "/felix/datasets/merge"
tags: ["felix", "datasets"]
---

# Merge Datasets

`POST /felix/datasets/merge`

Merge multiple datasets of the same type into a single new dataset.

Concatenates all rows from the source datasets into a new dataset.
All source datasets must share the same dataset_type (NER, classification, etc.).

Args:
    request: Merge request with source datasets and output name.

Returns:
    DatasetMergeResponse with the new dataset details.

## Request body

- DatasetMergeRequest — Request to merge multiple datasets into one.
  - `sources` DatasetMergeSource[], required — Datasets to merge (at least 2)
    - `dataset_name` string, required — Name of the dataset
    - `version` string — Version to merge (default: latest)
  - `output_name` string, required — Name for the merged dataset
  - `project_id` string, nullable — Project to assign the merged dataset to

## Response `200`

Successful Response

- DatasetMergeResponse — Response from a merge operation.
  - `success` boolean, required
  - `dataset_name` string, required
  - `version` string, required
  - `sample_size` integer, required — Total rows in the merged dataset
  - `source_counts` object, required — Number of rows contributed by each source dataset
  - `message` string, required

## Other responses

- `422` — Validation Error

---

[API](https://skmtc.net/pioneer/apis/brain-api.md) · [All operations](https://skmtc.net/pioneer/apis/brain-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/pioneer/brain-api/revisions/31dfe831e079/schema)