System Privilege To Enable and Disable Tracing
GRANT/REVOKE alter session TO uwclass;
Add time_statistics in trace file.
ALTER SYSTEM SET timed_statistics=TRUE;
SQL COMMANDS
ALTER SESSION SET sql_trace = TRUE;
ALTER SESSION SET sql_trace = FALSE;
Using PL/SQL CODE
trace enable
EXECUTE DBMS_MONITOR.SESSION_TRACE_ENABLE(7,4634, TRUE, FALSE);
trace disable
EXECUTE DBMS_MONITOR.SESSION_TRACE_DISABLE(7,4634);
Location of TKRPROF Utl.
$ORACLE_HOME/rdbms/admin/utltkprf.sql
Trace file location
$ORACLE_BASE/diag/orabase/orabase/trace
Sqlplus commandline
TKPROF c: emp\orabase_ora_1492.trc c: emp race_out.txt
To enable the SQL Trace Session from SQL prompt
EXECUTE DBMS_MONITOR.SESSION_TRACE_ENABLE(7,4634, TRUE, FALSE);
To disable tracing specified in the previous step:
EXECUTE DBMS_MONITOR.SESSION_TRACE_DISABLE(7,4634);
Taken from, for more details
trace_tkprof
