ORA-38713: Flashback Database logging is already turned on.
Cause: An ALTER DATABASE FLASHBACK ON command had no effect because flashback database logging was already on.
Action: No action required.
ORA-38713: Flashback Database logging 是 Oracle Database 中的一个错误代码，它表示当一个操作尝试在 Flashback Database 记录状态中变更一个已经存在的操作时触发。