qRFC is a layer between the application and tRFC. It only allows a LUW to be transferred to a target system if no predecessor LUWs exist in the participating queues. After a qRFC LUW has been executed, the QOUT Scheduler automatically executes the next qRFC LUW that is waiting in the queue.
qRFC with outbound queue enables serialization of the LUWs in the sending system. You can use qRFC with outbound queue with every tRFC-supported target system, because the sequence of the calls is established in the application program. The target system therefore does not require any knowledge about the serialization. This applies to SAP and non-SAP systems when using the RFC Library.
The main features of qRFC with outbound queue are summarized below:
· The queued RFC with outbound queue causes the pages of the sending system to be serialized. The target system has no knowledge of the serialization in the sending system. This means that it is possible to communicate with any SAP target system from release 3.0 onwards.
· A LUW (transaction) can be distributed between more than one queue. However, it is only transferred if all predecessor LUWs in all participating queues have been processed. After a qRFC transaction has been executed, the system tries to start all waiting qRFC transactions in sequence.
administration, each qRFC transaction requires a queue name and a queue
counter. Each tRFC call that needs to be serialized is assigned a to queue
name determined by the application. The application programmer specifies the
queue name when calling the function module TRFC_SET_QUEUE_NAME. This
occurs directly before each RFC call that needs to be serialized.
Because this is a logical queue, no queue configuration is required. In an SAP system there is only one table for all outbound queues. This table records the names.