Hi,
In Screen Shot above Lifbk is having BankKey 15 char and Z table 10 Char
1. select the data from Ztable, Since Bank Key is of 10 char
2. Compare BankKey of Lifbsk with Bankey of Ztable by extracting(offsetting)
wa_lifbk-bankkey(10) or Itab-Bankkey +0(10)