Passing slicer selection to REST API call in power query

Dynamic M Query Parameters only work with Direct Query data sources.  Your API isn't one.

Hi girlwonder 

As the lbendlin  mentioned, if you want to use the dynmaic paramater, you need to make sure that your connection mode is direct query, such as SQL database and so on, they can be connected by Power BI Desktop with direct mode, You can refer to the following link about the dynamic paramater.

https://learn.microsoft.com/en-us/power-bi/connect-data/desktop-dynamic-m-query-parameters#prerequisites

If you want to change the paramater with the import mode, it only can be changed in power query or In data source settings in Power BI Service, You can refer to the following link.

https://learn.microsoft.com/en-us/power-bi/connect-data/service-parameters#review-and-edit-parameters-in-power-bi-service

You can change the data source to the ones that support direct query mode. such as :

• SQL Server
• Azure SQL Database
• Azure Synapse Analytics (formerly SQL Data Warehouse)
• Oracle
• Teradata
• SAP HANA

Best Regards!

Yolo Zhu

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