More about trail files
Trail files are used by Extract and Replicat processes, and their primary role is for data persistence. One could argue that writing files to what could be deemed as a "staging area" is wasteful and suboptimal. That said, GoldenGate writes to trail files in large blocks minimizing I/O. Furthermore, the architecture provides a guaranteed no data loss solution that is not to be underestimated.
The trail
By default, trail files are in canonical format being unstructured with a header record. Each record is of a variable record length containing the changed data. A trail can contain numerous trail files each having a two-character prefix with a 6 digit sequence number suffix.
An Extract process can write data to many trails. A Replicat can process data from one trail. However, it is possible to configure multiple Replicat processes to handle the workload.
Trail file purging
To "clean up" the processed trail files from a given trail to reduce disk space usage, configure the...