When creating a manually-entered dataset in Pipeline Builder, you can generate notional data to populate your dataset.
To do this, inside your manually-entered dataset, select Generate notional data.

On the left side, select the column for which you want to generate data. Then, in the Auto populate with field, select the category of data that column should contain. To view examples of what the notional data would look like, select Examples.
To specify how many rows you want generated, you can enter a number between 1 to 1000 for the Pick number of rows field.

If you want to preview your manually entered table select Preview. This will open a new tab in the bottom panel called Preview generated data.
After you are finished with configuring your columns, select Generate table located on the right.
By default, Generate table will overwrite any previously-existing data in your manually-entered table.
If you want to keep the values of any columns, you can use the lock option located next to the specific column. When a column is locked, even when a table is re-generated, the values in that column will remain unchanged.

You can also use another dataset to generate a foreign key. This will link the dataset with a column from another dataset.
Other examples of data that can be auto-populated in Pipeline Builder include:
If none of the existing auto-population categories suit your needs, you can use a Large Language Model (LLM) to generate data based on your custom column description.
To select the LLM option, under Auto-populate with, choose Generate with LLM.

In the column prompt, enter a clear description of the data you want to generate. You can reference other columns by typing /[name of column]

Example cell values are highly encouraged to help the LLM understand the type and format of data you expect. You can provide examples of cell values for the LLM to reference in Example cell value.
Note that you can preview 10 rows at most for LLM-generated data.
Generating a large number of rows or using a complex prompt may take up to one minute.