Manually flush buffer cache & shared pool cache without bouncing the database:-
For Standalone Databases
alter system flush buffer_cache;
alter system flush shared_pool;
For RAC Databases
alter system flush buffer_cache global;
alter system flush shared_pool global;
------- only do in case of system performance issue or maintenance issue ----
Flush shared pool meaning flushing cached execution plan and sql Quries from memory.
Flush buffer cache meaning flushing cached data from memory.
Database restart which internally flush both
