Cluster linking key issue

I setup 2 on-premise confluent servers for testing the cluster linking. Using Oracle CDC to capture the table schema. Once mirror topic was created, found the all the values can be found from Oracle CDC. However, no key was found. In the mirror topic, just found a message contained all the values. How can I do? Thanks!

Hi, is the key present in the source topic? Do you mean the key of the topic’s message, or the key from the Oracle DB’s row?