Over the past few weeks I’ve spent some time playing around with Power BI custom data connectors and while I don’t have anything to share publicly yet (other people are way ahead of me in this respect – see the work of Igor Cotruta, Miguel Escobar and Kasper de Jonge among others) I have learned some interesting things that are worth blogging about.

First of all, the data privacy rules around combining data from different data sources do not apply in custom data connector code. As the docs say here:

Data combination checks do not occur when accessing multiple data sources from within an extension. Since all data source calls made from within the extension inherit the same authorization context, it is assumed they are “safe” to combine. Your extension will always be treated as a single data source when it comes to data combination rules. Users would…