In Oracle Database, hidden parameters are parameters that are not displayed in the list of parameters returned by the V$PARAMETER view. However, they can be very useful in certain situations, such as troubleshooting or performance tuning.
In Oracle Database, you can check hidden parameters using the following steps:
-
Log in to the Oracle Database as a user with SYSDBA or SYSOPER privileges.
-
Open SQL*Plus or any other SQL client and connect to the Oracle Database instance.
Suppose we need to find hidden parameter(_kks_use_mutex_pin) value in Database.
Execute Below Query:
SQL> select x.ksppinm name,y.ksppstvl value from
sys.x$ksppi x,sys.x$ksppcv y where
x.inst_id=sys_context('userenv', 'instance') and
y.inst_id=sys_context('userenv', 'instance') and
x.indx=y.indx AND
x.ksppinm = '_kks_use_mutex_pin';
If it's having value false and you want to change it to true.
Do the below:
SQL> alter system set "_kks_use_mutex_pin"=false scope=spfile;
SQL> shutdown immediate
SQL> startup
