How to develop this in transformer

[maheshkumar.bm]

Hi,I am junior developer and have problem.I have source data like above.Credit_id is increasing automatically
credit_id proposal_id
1 1
2 1
3 1
4 2
5 2
and i want to put this data to target like this
credit_id proposal_id credit_index
1 1 1
2 1 2
3 1 3
4 2 1
5 2 2
how can i do?
thanks for your helps

[chulett]

Start by posting your question in the correct forum.