v$rman_configuration - no rows selected

When you have default configurations for RMAN, then running of v$rman_configuration view will not give you any output. Once you touched any configuration item, then you able to see some outputs for this view.

Example:

My default config:

RMAN> show all;

using target database control file instead of recovery catalog
RMAN configuration parameters for database with db_unique_name TESTTMP are:
CONFIGURE RETENTION POLICY TO REDUNDANCY 1; # default
CONFIGURE BACKUP OPTIMIZATION OFF; # default
CONFIGURE DEFAULT DEVICE TYPE TO DISK; # default
CONFIGURE CONTROLFILE AUTOBACKUP OFF; # default
CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '%F'; # default
CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET; # default
CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE MAXSETSIZE TO UNLIMITED; # default
CONFIGURE ENCRYPTION FOR DATABASE OFF; # default
CONFIGURE ENCRYPTION ALGORITHM 'AES128'; # default
CONFIGURE COMPRESSION ALGORITHM 'BASIC' AS OF RELEASE 'DEFAULT' OPTIMIZE FOR LOAD TRUE ; # default
CONFIGURE RMAN OUTPUT TO KEEP FOR 7 DAYS; # default
CONFIGURE ARCHIVELOG DELETION POLICY TO NONE; # default
CONFIGURE SNAPSHOT CONTROLFILE NAME TO '/u01/app/oracle/product/12.1.0/dbhome_1/dbs/snapcf_testtmp.f'; # default

RMAN> 


and out put for v$rman_configuration is:

SQL> select NAME,VALUE from v$rman_configuration;

no rows selected


Now I am going to change some configuration and then you can see the difference:

RMAN> CONFIGURE RETENTION POLICY TO REDUNDANCY 2;

new RMAN configuration parameters:
CONFIGURE RETENTION POLICY TO REDUNDANCY 2;
new RMAN configuration parameters are successfully stored

RMAN> CONFIGURE CONTROLFILE AUTOBACKUP ON;

new RMAN configuration parameters:
CONFIGURE CONTROLFILE AUTOBACKUP ON;
new RMAN configuration parameters are successfully stored

RMAN> 

SQL> select NAME,VALUE from v$rman_configuration;

NAME                   VALUE
---------------------- ---------------------------------------------
RETENTION POLICY          TO REDUNDANCY 1
CONTROLFILE AUTOBACKUP    ON

SQL> 

Some times you need to reset the whole RMAN config with one shot, instead of running several clear commands like the following,
'RMAN> CONFIGURE BACKUP OPTIMIZATION CLEAR;' , simply run the RESETCONFIG.

SQL> EXECUTE DBMS_BACKUP_RESTORE.RESETCONFIG;
PL/SQL procedure successfully completed.

-- After executing this command, the v$rman_configuration view is empty, which means that all
-- RMAN persistent settings are default.

SQL> select NAME,VALUE from v$rman_configuration;

no rows selected

SQL>