.. _auto_dataset_get_unique_as_dataset:

*GETS UNIQUE VALUES OF A COLUMN*
================================

Extracts all unique (deduplicated) values from a specified column of an input dataset and returns them as a new single-column dataset. Use this worker when you need a distinct-values lookup table or want to enumerate categorical levels in a column.

When to use
-----------

Classification: **process**.

Tagged: ``column``, ``dataset``, ``deduplicate``, ``distinct``, ``transform``, ``unique``.

Inputs
------

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 20 20 20

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Dataset Name
     - datasetname
     - dataset
     - —
     - 
     - The source dataset whose column will be scanned for unique values; must contain the column specified in `column_name`.
   * - Column Name
     - column_name
     - scalar
     - —
     - 
     - Name of the column (string, case-sensitive) from which unique values are extracted; must match an existing column header in the input dataset.

Outputs
-------

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 20

   * - Label
     - ID
     - Type
     - Description
   * - dataset_unique_output_1
     - dataset_unique_output_1
     - dataset
     - A new dataset containing two columns — an auto-incremented integer `id` and the named column — with one row per distinct value found in the source column.

Disciplines
-----------

- data.dataset.transform

Runnable example
----------------

A runnable example is registered for this worker. Open the example workflow on the d3VIEW canvas: `/api/workflow/example?id=dataset_get_unique_as_dataset <https://www.d3view.com/api/workflow/example?id=dataset_get_unique_as_dataset>`_

.. raw:: html

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   Auto-generated from <code>transformation</code> schema. Worker id: <code>dataset_get_unique_as_dataset</code>. Schema hash: <code>021aff86b6f3</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
   </p>