While running CheckDB we were getting warning in system as
BR0978W Database profile alert - level: WARNING, parameter: OPTIMIZER_FEATURES_ENABLE, value: 8.1.7 (<> 9.2.0)
our database is running at version 22.214.171.124
In order to avoid this warning we have done changes in INITSID.ora and changed
parameter OPTIMIZER_FEATURES_ENABLE = 9.2.0 from 8.1.7
but after restart we faced major performance issue in the system and there are other 2 parameters
automatically got changed because of this change as mentioned below.
OPTIMIZER_DYNAMIC_SAMPLING got changed automatically from 0 to 1
OPTIMIZER_MAX_PERMUTATIONS got changed automatically from 80000 to 2000
Now we have reverted settings back to previous i.e OPTIMIZER_FEATURES_ENABLE = 8.1.7
Due to which other 2 parameters also changed back to original vlues 0 and 80000 automatically.
Kindly suggess what should be the correct value for this parameter OPTIMIZER_FEATURES_ENABLE if our database version