Update the database parameters
- Open a Command Prompt window.
- Log in to SQL*Plus with /nolog.
- At the SQL*Plus prompt, type the following commands in the order listed:
ALTER SYSTEM SET "_optimizer_cost_based_transformation"=LINEAR;
ALTER SYSTEM SET "_push_join_predicate"=TRUE;
ALTER SYSTEM flush shared_pool;
ALTER SYSTEM flush buffer_cache;
This resets the parameters to the default value. However, the old value for these parameters appears in the v$parameters listing until a system is rebooted to clear the state.