Trace Files -- 12 : Tracing a Particular Process

Unlike tracing for particular SQL statements, you can also trace by PID  (Oracle PID) or Server Process ID (SPID).

SQL> select s.sid, p.pid
  2  from v$session s join v$process p
  3  on (s.paddr=p.addr)
  4  and s.username = 'HEMANT';

       SID   PID
---------- ----------
 19    22

SQL> 
SQL> alter system set events 'sql_trace {process: orapid=22}';

System altered.

SQL> 
SQL> select s.sid, p.pid, p.spid
  2  from v$session s join v$process p
  3  on (s.paddr=p.addr)
  4  and s.username = 'HR';

       SID   PID SPID
---------- ---------- ------------------------
 14    26 3207

SQL> alter system set events 'sql_trace {process:3207}';

System altered.

SQL> 

Tracing for the processes is disabled with :

SQL> alter system set events 'sql_trace {process: orapid=22} off';

System altered.

SQL> alter system set events 'sql_trace {process:3207} off';

System altered.

SQL> 

Tracing seems to get disabled after the next SQL, not immediately.

Remember : This is SQL Tracing, not Optimizer Tracing.
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