Oracle can be forced to monitor all executions with one of the following statements:
alter session set events 'sql_monitor force=true';
alter system set events 'sql_monitor force=true';
In order to force monitoring an SQL statement identified by an SQL Id, one of the following statements will do:
alter session set events 'sql_monitor [sql:abc0123456789] force=true';
alter system set events 'sql_monitor [sql:abc0123456789] force=true';
Monitoring can be turned off with
alter system set events 'sql_monitor off';
Limits
The number of statement executions that will be monitored at a given time is limited to 20 times the number of cpus, but can be adjusted with the hidden init parameter_sqlmon_max_plan.
Statements whose execution plans exceed 300 lines are not monitored. This threshold can be altered with the parameter _sqlmon_max_planlines.
The minimal execution time of 5 seconds that an SQL statement must be running before monitoring kicks in can be adjusted with _sqlmon_threshold.