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We are connecting our PBI file to an existing dataset on a Premium workspace using the Power BI Service data connector (Open up Power BI Desktop>Get Data>Power BI Service). The existing dataset on the service is using Row-Level Security which uses the UserName() function in Dax. When I connect my new PBI file pointed to the service's dataset the UserName() is returning NT Authority\System. Has anyone run into this, how would I return the username of whomever is running the report? I assume since I am not logging into app.powerbi.com directly to access this dataset, it has no idea of who I am, so it's returning the System account. Anyone using this method with RLS and have a working solution?
@Anonymous,
I can reproduce your issue, I will consult this issue internally, and post back.
Regards,
Lydia
Any update to this? We have the same issue. Our Users work with Power BI Desktop using direct Connection to datasets in the service.
It has been a long time, but this issue still occurs.
It can be solved by adding a role to a dataset. It is very similiar to below case:
Using Username() in DAX with Row-Level Security | Microsoft Power BI Blog | Microsoft Power BI
It seems that with workspaces in shared capacities USERNAME() returns a guid value, while in Premium capacitites it returns "NT AUTHORITY\SYSTEM".