Error: F_JD20DB: DBMS Error

Issue

At refresh, the following error appears:

F_JD20DB: DBMS error [ORA-08181: specified number is not a valid system change number].

Environment

• Amazon-hosted databases

Resolution

Check the status of the manifest aggregator. Make sure that it is running and publishing.

Cause

When starting a refresh through the shell script, it invokes database code that discovers how far ahead the manifest aggregator has processed changes. It uses this information to align an SCN for the refresh and creates a job.

This setup is unique to Amazon. If the aggregator does not run or publish changes, the script to create the refresh job will have an SCN that is too old for the database to provide a consistent snapshot.