Ora-38706:cannot turn on Flashback DATABASE logging. Ora-38709:recovery area isn't enabled.

One: Problem description

Sql> ALTER DATABASE flashback on;
ALTER DATABASE Flashback on
*
ERROR at line 1:
Ora-38706:cannot turn on Flashback DATABASE logging.
Ora-38709:recovery area isn't enabled. Two: The cause of the error

There is no flash recovery zone path set

As shown in figure:

III: Solutions

Set the flash-back recovery area Path

Sql> alter system set db_recovery_file_dest= '/home/oracle/db_recovery_file_dest ';--you can customize the path here

System altered.

Sql> Show parameter db_recovery;

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
Db_recovery_file_dest String/home/oracle/db_recovery_file_
Dest
Db_recovery_file_dest_size Big Integer 2G
Sql> ALTER DATABASE flashback on;

Database altered.

--No more errors.