APPROACH FOR BDC PROGRAM

1. What should be the approach for writing a BDC program?

STEP 1: CONVERTING THE LEGACY SYSTEM DATA TO A FLAT FILE to internal table CALLED "CONVERSION".

STEP 2: TRANSFERING THE FLAT FILE INTO SAP SYSTEM CALLED "SAP DATA TRANSFER".

STEP 3: DEPENDING UPON THE BDC TYPE i)call transaction(Write the program explicity)

The legacy system data has to be converted to a flat file  and convert the flat file to a internal table. You need to  transfer the flat file into sap system which is called sap  data transfer.

CONVERTING THE LEGACY SYSTEM DATA TO A FLAT FILE to internal table CALLED "CONVERSION".
TRANSFERING THE FLAT FILE INTO SAP SYSTEM CALLED "SAP DATA TRANSFER".
DEPENDING UPON THE BDC TYPE
i)call transaction(Write the program explicity)
ii) create sessions (sessions are created and processed.if success data will transfer).

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