SQL> alter session set sql_trace=true;

Session altered.

SQL> select 'x' a from dual;

A
-
x

SQL> alter session set sql_trace=false;

Session altered.

SQL> host tkprof ora10g_ora_6104.trc ora_6104.prf sys=no

TKPROF: Release 10.2.0.3.0 - Production on Sun Sep 14 14:18:24 2008

Copyright (c) 1982, 2005, Oracle.  All rights reserved.

select 'x' a 
from
 dual


call     count       cpu    elapsed       disk      query    current        rows
------- ------  -------- ---------- ---------- ---------- ----------  ----------
Parse        1      0.00       0.03          0          0          0           0
Execute      1      0.00       0.00          0          0          0           0
Fetch        2      0.00       0.00          0          0          0           1
------- ------  -------- ---------- ---------- ---------- ----------  ----------
total        4      0.00       0.03          0          0          0           1

*** 2008-09-14 14:17:27.204
*** ACTION NAME:() 2008-09-14 14:17:27.198
*** MODULE NAME:(SQL*Plus) 2008-09-14 14:17:27.192
*** SERVICE NAME:(ora10g) 2008-09-14 14:17:27.192
*** SESSION ID:(142.214) 2008-09-14 14:17:27.192
=====================
PARSING IN CURSOR #1 len=22 dep=0 uid=61 oct=3 lid=61 tim=19381078997 hv=1629880439 ad='309f72c4'
select 'x' a from dual
END OF STMT
PARSE #1:c=0,e=37335,p=0,cr=0,cu=0,mis=1,r=0,dep=0,og=4,tim=19381078986
EXEC #1:c=0,e=55,p=0,cr=0,cu=0,mis=0,r=0,dep=0,og=4,tim=19381092630
FETCH #1:c=0,e=25,p=0,cr=0,cu=0,mis=0,r=1,dep=0,og=4,tim=19381092976
FETCH #1:c=0,e=5,p=0,cr=0,cu=0,mis=0,r=0,dep=0,og=0,tim=19381112466
STAT #1 id=1 cnt=1 pid=0 pos=1 obj=0 op='FAST DUAL  (cr=0 pr=0 pw=0 time=8 us)'
=====================
PARSING IN CURSOR #2 len=33 dep=0 uid=61 oct=42 lid=61 tim=19386683171 hv=525901419 ad='0'
alter session set sql_trace=false
END OF STMT
PARSE #2:c=0,e=229,p=0,cr=0,cu=0,mis=0,r=0,dep=0,og=0,tim=19386683166
EXEC #2:c=0,e=22,p=0,cr=0,cu=0,mis=0,r=0,dep=0,og=0,tim=19386684257