Mass change in data source & credentials

Hi , Anonymous 

According to your description, you want to muti-update the url in the conection string.

If this , i think you need to create  a parameter to manage the connection string.

For more information, you can refer to :
Deep Dive into Query Parameters and Power BI Templates | Microsoft Power BI Blog | Microsoft Power BI

Edit parameter settings in the Power BI service - Power BI | Microsoft Learn

And you can also try to use pipeline rules features to create  a parameter rule, for more information, you can refer to :
Create deployment rules Power BI Application lifecycle management (ALM) - Power BI | Microsoft Learn

And you can also try to use the rest api to try to update the parameter if on the Power Bi Service, for more information, you can refer to :
Datasets - Update Parameters In Group - REST API (Power BI Power BI REST APIs) | Microsoft Learn

Thank you for your time and sharing, and thank you for your support and understanding of PowerBI! 

Best Regards,

Aniya Zhang

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