Databases Reference
In-Depth Information
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if you add online log files in this manner, they will be created in the fast recovery area, but the Fra will not
know of their existence. so, they will not be counted toward the total number of files or the space consumed in the Fra.
this may cause you to miscalculate the Fra space, causing space starvation in Fra.
Caution
Using the following command, you can add a logfile group quickly without specifying anything else, such as the
group number:
alter database add logfile;
This will create a new log file group at a sequence of one more than the last log file group sequence. So, if
currently the group number of the last added log file group is 6, the previous command will add a group 7 with just
one file in the Oracle managed file format. You can check that through the following query:
SQL> select member
2 from v$logfile
3 where group# = 7;
MEMBER
-------------------------------------------------------------
+FRA/cdb1/onlinelog/o1_mf_6_2lrvlth1_.log
Adding a New Log File Group: Only One Member in the FRA
If you want only one member of the group in the fast recovery area and the other one in the regular database file
location, you should define two parameters: the fast recovery area and
db_create_file_dest
. This parameter
determines where a data file should be created if no location is given.
1.
Set the parameter where you want to create the first member of the online redo log
groups. To specify the location, such as the ASM disk group DATA, issue the following SQL
statement:
SQL> alter system set db_create_file_dest = '+DATA';
System altered.
Ensure that the parameter
db_create_file_dest
is set:
2.
SQL> show parameter db_create_file_dest
NAME TYPE VALUE
------------------------------------ ----------- -----------------------------
db_create_file_dest string +DATA
Like the fast recovery area, the directory you specify as a location of the previously mentioned parameter must
already exist. Oracle will not create it for you.
