You can join a hierarchy and the detail table in an Application Source Qualifier to extract table data along with hierarchy metadata. A hierarchy definition can only appear as the first object in the ABAP program flow.

When you join a hierarchy and a detail table in an Application Source Qualifier, the Designer generates open SQL to extract table data. Because the hierarchy is a structure of metadata, you cannot access it through SQL.

When you run a workflow, the ABAP program uses SQL to extract data from the detail table. The PowerCenter Integration Service calls an RFC function on the application server to extract the hierarchy metadata. The PowerCenter Integration Service then joins the hierarchy and detail data.