> For the complete documentation index, see [llms.txt](https://documentation.astera.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://documentation.astera.com/dataprep/reading-sources/reading-a-dataset.md).

# Reading a Dataset

In Astera Dataprep, the dataset that is most recently loaded becomes the current dataset meaning any transformation, filter, or cleansing steps you apply next will target this one. If you want to apply operations on a previously loaded dataset instead, you can use the *Read Dataset* step to bring it back as the current dataset.

This allows you to:

* Reuse a cleaned dataset from earlier in your dataprep flow.
* Switch focus from one dataset to another without reloading the file.
* Ensure your transformations apply to the right data.

### Option 1: Read a Dataset Using Chat

Simply type your request in the Dataprep chat, such as asking to apply a transformation to a previously used dataset. It will automatically reload that dataset and perform the requested operation.

![](/files/kZLvHBx4WQrjfpUw1DeJ)

### Option 2: Toolbar Method

1. Open Astera Dataprep.

![](/files/nR5n4Br0KW3xR76zf3nY)

2. Navigate to the Toolbar and select **Read > Dataset**.

![](/files/7xtP1hEpGshJB17KrJA1)

3. Configure the following options in the dialog:

* **Name**: From the dropdown, choose the name of the dataset you want to use. This dropdown shows you all the available datasets in the project.

![](/files/HXSL5xPyOO0QNt6yisAp)

4. Choose the Dataset you want to read and click **Apply** ![](/files/10KTRq7DN4pST0pzbGYQ) to apply the changes or **Cancel** ![](/files/e4f4rMvxRFqqVuMC37UI) to discard them.
5. Once you click *Apply*, your selected dataset is now the current one. You can continue performing any transformations, joins, validations, or data quality operations on it.

![](/files/ATYMpHEpGKZr4980Q1t0)

This concludes the document on reading a Dataset in Astera Dataprep.


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