SQL> col name format a30
SQL> col value format 999,999,999
SQL>
SQL> -- 1. 1st snapshot
SQL> col value new_value prev_value
SQL> select s.sid, n.name, s.value
  2    from v$sesstat s,
  3         v$statname n ---------<<<<<<<<<<<<<<< stat명으로 비교하기 위해 조인
  4   where s.statistic# = n.statistic#
  5     and s.sid = userenv('sid')
  6     and n.name = 'session logical reads';

       SID NAME                                  VALUE
---------- ------------------------------ ------------
       151 session logical reads               249,004

SQL>
SQL> -- 1-1. save 1st snapsho
SQL> prompt &prev_value
249004

SQL> -- 2. Workload Process
SQL> select count(*) from all_objects ;

  COUNT(*)
----------
     45943

SQL>
SQL> -- 3. 2nd snapshot
SQL> col value new_value next_value
SQL> select s.sid, n.name, s.value
  2    from v$sesstat s ,
  3         v$statname n
  4   where s .statistic# = n.statistic#
  5     and s.sid = userenv('sid')
  6     and n.name = 'session logical reads';

       SID NAME                                  VALUE
---------- ------------------------------ ------------
       151 session logical reads               322,437

SQL>
SQL> --  3-1. save 2nd snapshot
SQL> prompt &next_value
322437

SQL> -- Diff
SQL> select (&next_value - &prev_value) as diff from dual;
구   1: select (&next_value - &prev_value) as diff from dual
신   1: select (    322437 -     249004) as diff from dual

      DIFF
----------
     73433