Hi, @Anonymous
I think you may have misunderstood the concept of dataset. In PowerBI Service, a dataset is a collection of datasource that you import or connect to in PowerBI Desktop.
In the PowerBI Desktop, you can connect multiple data sources (excel, csv, database, web, powerbi datasets ...) and even can integrate them into the same query. But once you upload the reports to the service, they will only be found in the same dataset . Similarly, when you download pbix from the service, you can see the data source information used to create the report in the report.
You can refer to these links.
https://community.powerbi.com/t5/Service/Difference-between-data-source-and-data-set/m-p/531191
https://docs.microsoft.com/en-us/power-bi/fundamentals/service-basic-concepts#datasets
Best Regards,
Community Support Team _ Eason
