> For the complete documentation index, see [llms.txt](https://docs.unitlab.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.unitlab.ai/documentation/datasets/attach-datasets-to-projects.md).

# Attach datasets to projects

Attaching a dataset is the boundary where durable membership becomes project work. Validate the source version and resulting Data Units before annotation begins.

### Before you make the change

* Choose the exact dataset version and project.
* Confirm the project ontology and workflow are ready for the incoming modality and group structure.
* Understand whether attachment creates, reuses, or updates Data Units in the current project state.

![Project Data page after dataset attachment](https://292810646-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FGjVLUz4wthGkGlRKM6rM%2Fuploads%2FsJhHsK7YkhabBtix4o95%2Fproject-data.png?alt=media\&token=06bd10a9-5d5a-4680-a807-d0fc697c37ac)

*After attachment, use Project Data to reconcile source membership with created work items and current workflow state.*

### Understand the product behavior

The project-side Attach Data modal has **Folders** and **Datasets** tabs; there is no loose Assets tab. Organize loose assets into a folder or dataset first.

1. The user opens **Attach Data**.
2. The user selects a workspace folder or a published dataset version.
3. Sources already fully attached are pre-checked, locked, and labeled Attached. This state is evaluated per version, so attaching v1 does not block v2.
4. Unitlab previews item and deduplication counts.
5. Commit clones the frozen version into the project as Unassigned data without re-uploading the files.
6. The newly attached items are selected automatically.
7. The Assign Members modal opens so annotator/reviewer assignment can continue immediately.

Attaching a folder first resolves it through a folder-backed dataset and frozen version. Attaching another project’s data includes only that project’s own source data; sources that were merely attached into that project do not cascade into the next project.

### Project dataset cards, View Source, and Detach

The project’s own data and every attached version appear as uniform dataset cards. Root-card actions include:

* **View Source** — opens the underlying project dataset, folder, or frozen version without mutation;
* **Detach** — removes that source from this project only.

Detach shows source name, asset count, and annotation count. By default it archives the project copies while preserving annotations. The user can explicitly choose **Clear annotations**, which requires a stronger confirmation. Re-attaching restores the archived project rows and kept histories instead of creating duplicates. Other projects and the Data Assets source remain unchanged.

### Attach and reconcile membership

{% stepper %}
{% step %}

#### 1. Select the project

Confirm project identity, purpose, ontology, workflow, and current operating state.
{% endstep %}

{% step %}

#### 2. Choose the dataset version

Use the explicit published version rather than a similarly named dataset.
{% endstep %}

{% step %}

#### 3. Attach the source

Start the operation and monitor any asynchronous processing.
{% endstep %}

{% step %}

#### 4. Reconcile Project Data

Compare expected item count, group behavior, modality, status, and source links.
{% endstep %}

{% step %}

#### 5. Open representative work

Verify the native Workbench and ontology load correctly before assigning volume.
{% endstep %}
{% endstepper %}

### Decisions that affect production

| Decision     | Production guidance                                                               |
| ------------ | --------------------------------------------------------------------------------- |
| Version      | Use the version approved for this project and record it in the change log.        |
| Duplicates   | Define whether already-attached items are skipped, reused, or require correction. |
| Grouped data | Confirm one group produces the intended project unit and layout.                  |
| Rollback     | Know whether detaching removes future availability only or affects active work.   |

### Continue the operating flow

* Write Project Instructions.
* Calibrate the Workbench on representative items.
* Assign work only after Project Data reconciliation.