Hi >How to change the activation_level for each statistics name given below here? > >SQL> select STATISTICS_NAME,ACTIVATION_LEVEL from v$statistics_level; > >STATISTICS_NAME ACTIVAT >---------------------------------------------------------------- ------- >Buffer Cache Advice TYPICAL >MTTR Advice TYPICAL >Timed Statistics TYPICAL >Timed OS Statistics ALL >Segment Level Statistics TYPICAL >PGA Advice TYPICAL [snip] Some statistics can be activated/deactivated separately through INIT.ORA parameters (e.g. DB_CACHE_ADVICE, TIMED_STATISTICS), i.e. the Reference Guide is your friend. Some undocumented parameters exist as well. Regards, Chris