How to get Power BI Usage across Multiple workspaces using Lakehouse as source

Hi powerbihelp87,
Thanks for reaching out to the Microsoft Fabric Community forum.

According to my understanding and according to Microsoft documentation, the Power BI Admin and Activity Events REST APIs are limited to Power BI artifacts and capture usage only for reports, dashboards, datasets (semantic models), dataflows, and Power BI apps, including app consumption. These APIs do not capture Microsoft Fabric workload telemetry such as Lakehouse, Warehouse, Notebook, or Pipeline usage. 

Even when a Power BI report is built on top of a Lakehouse, the APIs record only the report‑level activity and do not expose any underlying Lakehouse table reads or queries. Microsoft tracks Fabric workload usage separately through Fabric‑specific tools such as the Fabric Monitoring Hub and Fabric Capacity Metrics. 

In practice, Power BI Admin or Activity Events APIs should be used for report‑ and app‑level usage across workspaces, while Fabric Monitoring and Capacity Metrics should be used for Lakehouse, Warehouse, Notebook, and Pipeline usage. Currently, there is no single API that combines both Power BI usage and Fabric workload telemetry.

For your reference:
https://learn.microsoft.com/en-us/rest/api/power-bi/admin
https://learn.microsoft.com/en-us/power-bi/guidance/admin-activity-log
https://learn.microsoft.com/en-us/fabric/admin/monitoring-hub
https://learn.microsoft.com/en-us/fabric/enterprise/metrics-app

I hope this information helps. Please do let us know if you have any further queries.
Thank you