> For the complete documentation index, see [llms.txt](https://docs.cloudio.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.cloudio.io/creating-datasources/working-with-datasources/creating-a-data-source/defining-server-side-validations/adding-conditional-defaulting-rules.md).

# Adding conditional defaulting rules

You can define default attribute values for a given condition.

For example, if you want to populate the end date field when the Active checkbox is selected in the user interface, add the following validation script at the before insert and before update level.

```
String active = data.get("active");
String oldActive = null;
 if (dbdata != null) {
    oldActive = dbdata.get("active");;
}
if ("N".equals(active)  && (oldActive == null || "Y".equals(oldActive))) {
   data.set("endDate", new Date());
}
```

{% hint style="info" %}
**Note**: dbdata is available for the update scripts and has the values fetched from the database. You can use it to compare the old values to the values updated by the user.
{% endhint %}


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