Show TOC

 External Data Transfer with Function Modules


SAP provides function modules for transferring plan and actual data from external or legacy systems. You call up these function modules in a program that you have to create yourself.

Note Note

With effect from Release 4.6A, SAP also provides Business Application Programming Interfaces (BAPIs) for transferring external data. SAP recommends using BAPIs so that you can transfer external data into the SAP System without the need for programming.

End of the note.


Since you need to create your own program (containing all the necessary steps for data transfer) for transferring external data using function modules, you should have previous experience in ABAP programming.

To simplify the external data transfer process, SAP demonstration programs are available. These programs contain sample calls of the function modules, which control the data transfer.


You can transfer plan and actual data from external or legacy systems into the SAP System using function modules.

You can carry out Plan Data Transfer by calling up the appropriate function module directly in the program. The SAP System carries out all the checks on the data to be transferred in a plan data transfer using function modules.

You can carry out an actual data transfer in the background, or by using immediate update. The function modules transfer the data directly to the corresponding screens . The SAP System performs checks on the screen, and not while the function module is being processed. This enables you to analyze any errors that occur. There are three SAP demonstration programs for actual data transfer, which include important steps for the transfer of actual data.

When you transfer external data to the SAP System (for example, from a sequential file with a specific structure), you need to change the data structure to conform with the existing SAP structure. This means that you assign the external data to the fields in the SAP structure.

The program for the external data transfer must contain the following steps:

  1. Read the data records to be transferred

  2. Transfer the data to an internal table with an SAP-defined structure

  3. Transfer actual or plan data using demonstration programs.