Oracle Error Message
ORA-31427: publication string already subscribed
Reason for the Error
The subscription already contained this publication.
Solution
Check the values of subscription_name and publication_id. Check any other subscribe calls to see if they subscribe to columns that are shared among more than one publication on the same source table. Do not attempt to subscribe to the same publication more than once in the same subscription. Use the publication_id variant of the SUBSCRIBE call if needed to specify precise publications.