Reports are published with connection details of shared data sources and they are stored in a common folder called data sources. However, during the publish, developer has a freedom to change the default folder for data sources for the solution, hence additional folders that hold data sources in the portal is not unusual.
There is no specific routine or pre-processes done for managing data sources. If all data sources are stored in the standard
Data Sources folder, you will work with that folder, else you will be working with multiple folders. When you open the portal, you can see the folder as shown in the following screenshot:
If you open the folder, you can see data sources added from all solutions. ...