Hi Radhika,
Using dummy field for Time stamp / date won't solve your problem. For delta to trigger, value of those fields must be changed or updated whenever you create or change corresponding document.
Below are few options for your requirement:
1.
Here you need to understand relationship between tables. As you have given example of VBPA table.
VBPA does not have any date or timestamp related field, but it works along with VBAK & VBAP tables as all these tables have common VBELN (Sales Document) as primary key. So you have VBAK & VBAP with delta specific fileds.
So whenever any new document is created or changed in VBAK & VBAP, your delta logic should pick up those records from VBAK & VBAP tables and along with this you need to pick the corresponding records from VBPA table using VBELN field. This is how your delta logic will work. You need not to have separate delta specific field in VBPA.
You can get table relationship information from functional consultant.
On parallel lines you need find relationship between other tables & prepare the logic for delta trigger.
2.
Then also if you need to build delta logic for VBPA table then in that case you can use two tables CDHDR & CDPOS. In these two tables changes in the ECC tables get stored along with change date.
On SDN you can find information about the working of CDHDR & CDPOS tables.
But these table has performance issue as most of the ECC table changes get recorded in these two tables.
Hope this 'll solve your problem.
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Thanks & Regards,
Pradip Nikam