VBKD table not updated while on order change
I have a requirement to update the VBKD table while we are going change the order line item.
Means when we create a new order with line item number the header label only getting update in VBAD along with VBAK and VBAP table's.
In header label update in VBKD table value will be in field posnr = 000000.
While we go for a item label change the VBKD table will update like Posnr = 10,20,30......
But in VA01 and VA02 in our system have done customized two tab name as a Additional A and Additional B in Additional B tab sales district field is there VBKD-BZIRK if we go for change sales district field value its not updating in VBKDtable but its updating in VBAP- ZZBZIRK field.
So below logic i need to write fr this requirement.
Compare the value of VBAP-ZZBZIRK with VBKD-BZIRK,
If the values are same, no actions needs to be taken,
If the values are different, check already entry is available in VBKD-POSNR for VBAP-POSNR.
Entry is available in VBKD, change the value of VBKD- BZIRK filed value with VBAP-ZZBZIRK. The entry is not available insert the new entry with VBKD-POSNR with VBAP-POSNR, copy all the field values except VBKD-BZIRK, move the VBAP-ZZBZIRK filed value to VBKD-BZIRK.
Anybody can help me for this requirement where i need to write logic and find below attachment for VA02 additional tab's.