After a database error, the database system writes diagnosis files (backups of the most important log files and memory dumps) to a special directory. You can configure the path of this directory with the special database parameter DIAG_HISTORY_PATH.
In this way, the database system ensures that when the database instance restarts, no important information for error analysis is overwritten.
See also:
Database Manager GUI, Diagnosis Options
Database Manager CLI, diag_histlist
Concepts of the Database System,