OTBI Report with two subject areas that are not connected

Summary:

I am trying to build a report that provides information on intercompany invoicing with details of the time entries, comments and costs associated with it. I am using the "Project Billing - Invoices Real Time" for invoice related information and the two OTBI subject areas, , "Project Costing - Actual Costs Real Time" and "Project Billing - Revenue Real Time" for reporting costs, actual labor hours, comments etc. These two reports do have a common link, but that is limiting. The common link is the intercompany record which unfortunately does not have the labor hours, costs or comments.

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