Using the qRFC with the RFC Library 

If your SAP application works with an external tRFC server using the RFC Library (RFC SDK), instead of tRFC functionality you can use qRFC with the outbound queue for LUW serialization. This procedure achieves better performance in the sending system.

You can also use an external RFC program in the client role to send a qRFC call to the inbound queue of an SAP system.

Restrictions

●      No implicit qRFC functionality is available using RFC SDK on the external RFC program page. qRFC calls are handled like tRFC calls here.

●      Unlike tRFC/qRFC between SAP systems, a LUW from a qRFC client program can contain only one RFC function.

Procedure

External RFC Server

No further activities are required for communication with an external RFC server.

External RFC Client

Depending on whether you use classic RFC SDK or NetWeaver RFC SDK, different activities are needed to set up qRFC communication for an external RFC client.

Classic RFC SDK

The conversion to qRFC functionality does not require much effort:

●      Minimal changes are required in the ABAP code.

●      No changes are required in the code on the tRFC server.

Execute the following steps to call an SAP system using qRFC from an external RFC program:

       1.      Instead of RfcIndirectCall or RfcIndirectCallEx, a tRFC client program has to use the new call RfcQueueInsert to prompt the target SAP system to save the inbound LUW in the defined inbound queue for subsequent processing.

       2.      As soon as the RfcQueueInsert call has been returned successfully, execute RfcConfirmTransID. If the call was successful, RfcQueueInsert must be repeated with the same TID.

NW RFC SDK

If you use NW RFC SDK then no changes are required regarding tRFC functionality. tRFC and qRFC calls are executed using the same NW RFC SDK transactional calls. For a qRFC call you only have to specify the queue name with which the call is to be saved in the inbound queue of the target system. 

Result

Once this call has been executed successfully, the LUW is saved completely in the inbound queue. The qRFC client can then refresh its own TID management (for example, by deleting obsolete TID entries).

 

If the target SAP system does not support qRFC with inbound queue, it processes the inbound LUW immediately and does not return an error message to the qRFC client program. If this happens, the qRFC client program works in the same way as a tRFC client program.

More Information

Documentation on SAP NetWeaver RFC SDK:

●      http://service.sap.com/connectors  → RFC Library → SAP NetWeaver RFC Library → SAP NetWeaver RFC SDK Guide.pdf

You can find more detailed information about the classic RFC SDK in:

●      RFC API