> ## Documentation Index
> Fetch the complete documentation index at: https://arizeai-433a7140.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# 11.25.2025: Split Assignments When Uploading a Dataset

> Available in Phoenix 12.18+

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With this update, Phoenix supports providing split labels during dataset upload — so you don't have to assign splits manually after uploading.

Once uploaded, you can immediately filter, query, or use those splits in experiments and evaluations. This streamlines data-preparation workflows and removes an extra manual step when organizing datasets for training, evaluation, or analysis.

<Card title="Pull Request #10353" href="https://github.com/Arize-ai/phoenix/pull/10353" icon="github" horizontal>
  GitHub
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