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Oracle: DBMS_MONITOR.SESSION_TRACE_ENABLE and SESSION_TRACE_DISABLE

SESSION_TRACE_ENABLE

session_trace_enable has the following parameters:
session_id binary_integer
serial_num binary_integer
waits boolean
binds boolean
plan_stat varchar2
Since all parameters have a default value, session_trace_enable can be simply invoked with 
begin
   dbms_monitor.session_trace_enable;
end;
/

See also

The init parameter sql_trace
Trace files
dbms_monitor

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