> For the complete documentation index, see [llms.txt](https://docs.fabricplan.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fabricplan.com/documentation/plan/planning-sheets/how-tos/persist-planning-data-using-writeback/configure-advanced-settings.md).
# Configure advanced settings
Under **Advanced settings**, you can control validation rules, and rename writeback columns. These options help you manage what data gets written back and how it is stored in the destination.
### 1. Validate writeback columns
In the **Advanced** tab, you can enforce validation rules on data before it is written back. You can use a null check or a formula-based condition.
**1.1. Cannot be empty**
Use **Cannot be empty** to write back only the cells that are not null for the selected field.
**1.2. Enter formula**
Use **Enter formula** to define a formula that must evaluate to true for cells to be written back. Cells that do not meet the validation rule are excluded during writeback.
You can also apply cross-filters. During writeback, the system shows a preview of excluded cells.
**1.3. Prevent writeback when validation fails**
Turn on **Prevent writeback when validation fails** to stop writeback when empty fields are detected. When validation fails, the system generates an exception notification with details about the empty measures, columns, or rows that do not meet the validation condition.
### 2. Rename writeback columns
You do not need to use the source dataset column names during writeback. You can specify a custom column name for the writeback table.
To rename columns, go to **Writeback settings > Advanced** and select **Writeback column rename**.
{% hint style="info" %}
Use standard database naming conventions, such as `snake_case` or `PascalCase`, to ensure compatibility with your destination database.
{% endhint %}
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