You should be able to relate data connections to workbooks based on the data_connections table in the repository. It looks like the [owner_id] field should join to the workbook table:
owner_id integer The ID of the workbook or datasource that is creating the data connection.
One thing to note is that data sources are not always paired to workbooks because they can be published separately. So this might be a good start to a impact analysis. I'm not sure you can link a DS to a view level though based on how I understand the workgroup data dictionary; while you can link views in the workbook and suggest that DS that are tied to the workbook potentially impact the view, i don't think there is an obvious dependency key we can rely. Part of this design might be how data sources can influence views even when the view is not strictly "dependent" on a DS; blending or filter actions might pass values/parameters on the worksheet but don't form a strict dependency to that data source.
Thank you it is very helpful