Databases Reference
In-Depth Information
3.
Make sure the fast recovery area is set:
SQL> show parameter db_recovery_file_dest
NAME TYPE VALUE
----------------------- ------ --------- ------------
db_recovery_file_dest string +FRA
4.
Unset log destinations:
SQL> alter system set db_create_online_log_dest_1 = '';
System altered.
SQL>alter system set db_create_online_log_dest_2 = '';
System altered.
Note these are two consecutive single quotes.
With this configuration, if you decide to add a log file group, the group will be created with
two members, and they will be in the fast recovery area and the directory specified by
db_create_file_dest
. Let's see how that is done:
1.
First add a log file group:
SQL> alter database add logfile group 7;
2.
Check how many members are created and where:
SQL> select member
2 from v$logfile
3 where group# = 7;
MEMBER
MEMBER
--------------------------------------------------------------------------------
+DATA/cdb1/onlinelog/group_7.278.790292907
+FRA/cdb1/onlinelog/group_7.264.790292907
3.
In the physical fast recovery area location and in the view V$LOGFILE, verify the existence
of the new redo log files.
How It Works
One of the lesser known features of Oracle database administration is the ability to create data files, online redo
log files, and so on, without specifying file names and locations. You do this by specifying some locations in the
initialization parameter file as the location for these files. These locations could be ASM disk groups or file systems
or directories under file systems. The location must be available to all instances in case of a Real Application Cluster
(RAC) database. Please note that the directory you specify as a location must already exist. Oracle will not create it for
you. If you have defined the fast recovery area, the redo logs will be created there.
