During external data transfer, one distinguishes between
The SAP System carries out the same checks of the data to be transferred as those found in the corresponding dialog functions.
The transfer of external data to the SAP System requires ABAP/4 experience in order to create your own transfer program. SAP provides sample programs to make your work simpler in this regard. These programs contain callups for function modules that control the data transfer.
Detailed information on the procedures and execution of external data transfer can be found in the R/3 Library in "External Data Transfer" under "CO - General System Administration: Overhead Cost Controlling".