I'm submitting my solution for implementing SCD-2. Please refer the attached diagram below. I'm doing a equi join on the Stage and target table. For the first time load, I'm taking the left outer dataset and inserting into the target. Then I'm using MD5 function to generate a checksum for all the qualifying columns on stage and target table. If the records match then using the Checksum of stage and target , Upsert is decided.