Obsolete data sources in dataflow lineage

Hi FrankPreusker , thanks for sharing this link. Wasn't easy but it ended up working for me at the end.  I'll share my experience, hoping it can help others.

If like me your solution is 100% cloud based, you can skip to the very end of the page Frank refered to in his previous message because it's all for On-premises datasource... except for the "Purple Note" at the bottom on the page. I followed the instructions from that note and it worked !  Not easy I must say, but hey, better then nothing.

My case is a 4 year old dataflow that has a tone of old connections artefacts :

The current Query is has simple as it gets.  It uses one connection to another dataflow from another PBI env. There's not trace anywhere of the connections you see in the lineage.

The instructions say : "To remove this connection, in the Power BI service, select the settings icon, go to Manage Connections and Gateways > Connections select the ellipsis menu by the connection name, then select Removeto remove the old/unused data source connection". 

The challenge here is to figure out which connections are "old/unused", so you can safely delete. Because I'm the main developper of this solution since it started 4 years ago, I have a pretty good idea. But that screen had 38 connections listed and I can see how it could get daunting. 

HINT! Something I discovered later. The little circular arrows under the Status column are buttons that allow you to check the connection status. And you can even get more details on the status by clicking on it after it displays. It not bullet proof method but I think it helps in the decision making regarding which connections you can safely delete.

I did all the deleting I thought was OK (I kept 10 of the 38, not bad for a 4year old clean up). Then I went back to the lineage view and it was all clean !

Note that I didn't even have to do this part of the instruction : "Then go to the Home page, select the workspace, select the dataflow to open it, and then in the Table name page, select Edit tables. Then in the Power Query editor, select Save & Close for the dataflows to be updated to the current data source connection and to remove the older connection."

Also note that the active datasource is not showing. I think that's because connections to another dataflow from another PBI workspace is current not supported in the lineage view... sounds weird right? Let me know if you know more about that last point.

Hope this can help someone.

Have a nice day,

--mo