If the mapping requires an ABAP program, select the appropriate reader to run the session. The reader for an SAP session determines the work process under which the SAP application server extracts data.

You can run the session in one of the following modes:

For a mapping with an ABAP program, you select stream or file mode when you generate and install the ABAP program.

If the mapping contains a hierarchy only, you can run the session in stream mode or file mode. If the mapping contains a hierarchy or IDoc definition, the PowerCenter Integration Service makes a remote function call to extract the hierarchy data.

If the mapping contains a hierarchy definition and the detail table definition in one Application Source Qualifier, the ABAP program that extracts the detail table data also joins the detail data to the hierarchy data extracted through the remote function call. Select the SAP Staging Reader if the mapping contains both a hierarchy and detail table definition.

Although you can choose SAP Streaming Reader or SAP Staging Reader as the reader type in the session properties, the PowerCenter Integration Service always extracts hierarchy data through RFC.

The following table shows properties for file and stream mode sessions:

You can configure the session to load data to the SAP tables. The PowerCenter Integration Service sends data to the SAP system as packets. The SAP transport module loads data to the SAP tables either as bulk mode or normal mode based on the sessions configuration. SAP tables include transparent, pool, and cluster tables.