> 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/astera-data-stack-v10/faqs/workflows/can-i-perform-an-action-based-on-whether-a-file-has-data.md).
# Can I perform an action based on whether a file has data?
Yes, you can perform workflow actions based on the decision whether a file has data or not. This can be done using an Aggregate object in a dataflow to calculate record count and pass it as an output variable in the workflow.
Dataflow:
Workflow:
The following steps allow you to perform workflow actions based on whether a file has records or not:
* In the dataflow, map a source field to an Aggregate transformation, setting the aggregate function for that field to Count.
* Then, map that field from the Aggregate transformation to an Expression where you would set this field to a variable.
* Define an output variable for this field in a local variables object.
* In your workflow, configure a Run Dataflow Task for your dataflow, the output variable will appear in the object.
* Place a Decision task after the Run Dataflow task.
* Specify the condition that Count variable should be greater than 0.
* Map the Yes port to the task that should be performed if the file has records.
* Map the No port to the task that should be performed if the file does not have records. Either of these ports can be left unmapped if you don’t want a task to be performed for that decision outcome.
> Note: This process might impact performance when handling large datasets. Although we only need to determine if there are any records (0 or more), the system will process the entire dataset.
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