BDC doubt.......

Hi,

I have to write a BDC which will update vendor master data for transaction FK01.

User enters in FK01 and enetsres data in NAM1 and STREET field everyday. In the evening we need to write a BDC which will copy NAME1 to NAME3 and

STREET to STREET4. These BDC will run in a scheduled manner.

How can we proceed with this ? What is the role of program RFBIKR00 in this and whats the meaning of PERFORM INIT_BGR00(RFBIKRI0) USING BGR00.

Please guide.