Hi @Deb
Yes, I wrote on article for doing CDC with NiFi for a MySQL database:
https://community.hortonworks.com/articles/113941/change-data-capture-cdc-with-apache-nifi-version-1...
NiFi doesn't currently support MS SQL, but it appears there is a NiFi contributor who has it in the works:
https://github.com/apache/nifi/pull/2231
Not sure if the solutions uses transactional logs or not.