Connect Two Subject Areas Without Common Attribute or Dimension in OTBI (Answers Report)

Hello experts,

I need assistance with connecting data from two different subject areas for a report in OTBI:

• Receivables - Transactions Real Time
• Subscription Management - Subscription Billing Real Time

Unfortunately, I couldn't identify any official common dimension to make the join work properly. However, I know that the fields "Transaction Number" (from Receivables) and "Invoice Number" (from Subscription Management) contain the same IDs, which should logically serve as a matching point.

I attempted to filter the report using a condition where "Transaction Number" = "Invoice Number", but this resulted in an error.

Is there a way to manually connect these two fields to enable a correct join between the subject areas? Any guidance would be greatly appreciated!