Dillema in selecting Delta Specific Field

Hi Gurus,

I have stuck in a situation and would heavily appreciate your help.

I have created a Generic datasource ZAFRU which extracting data from AFRU table.

I used Last Changed On (LAEDA) as delta specific field but later i found it is not working because more than 50% of records dont have last changed on date (LAEDA) in it.

So, later i used Posting Date (BUDAT) as delta specific field but still facing a problem. Like, suppose there is a service order which is posted three months ago but changed 5 days ago so delta will not capture the changed record as posting date (BUDAT) is not changed but only Last Changed On date (LAEDA) is changed.

In this way i am not able to use either fields as delta specific fields.

Also, can't use timestamp for delta specific field as it is not present in AFRU table and Document number also as it is blank for all the records.

Please suggest what should i use in delta specific field so that i should not miss any record in BI.

Thanks,

Saurabh