-- | PURPOSE  : List all currently connected user sessions ordered by the       |
-- |            number of transactions.                                         |
-- | NOTE     : As with any code, ensure to test this script in a development   |
-- |            environment before attempting to run it in production.          |
-- +----------------------------------------------------------------------------+


SET PAGESIZE 9999

COLUMN sid               FORMAT 99999            HEADING 'SID'
COLUMN serial_id         FORMAT 999999           HEADING 'Serial#'
COLUMN session_status    FORMAT a9               HEADING 'Status'          JUSTIFY right
COLUMN oracle_username   FORMAT a12              HEADING 'Oracle User'     JUSTIFY right
COLUMN os_username       FORMAT a9               HEADING 'O/S User'        JUSTIFY right
COLUMN os_pid            FORMAT 9999999          HEADING 'O/S PID'         JUSTIFY right
COLUMN session_program   FORMAT a20              HEADING 'Session Program' TRUNC
COLUMN session_machine   FORMAT a14              HEADING 'Machine'         JUSTIFY right TRUNC
COLUMN num_transactions  FORMAT 999,999,999,999  HEADING '# Transactions'

prompt 
prompt +----------------------------------------------------+
prompt | User Sessions Ordered by Number of Transactions    |
prompt +----------------------------------------------------+

SELECT
    s.sid                sid
  , s.serial#            serial_id
  , lpad(s.status,9)     session_status
  , lpad(s.username,12)  oracle_username
  , lpad(s.osuser,9)     os_username
  , lpad(p.spid,7)       os_pid
  , s.program            session_program
  , lpad(s.machine,14)   session_machine
  , sstat.value          num_transactions
FROM 
    v$process  p
  , v$session  s
  , v$sesstat  sstat
  , v$statname statname
WHERE
      p.addr (+)           = s.paddr
  AND s.sid                = sstat.sid
  AND statname.statistic#  = sstat.statistic#
  AND statname.name        = 'user commits'
ORDER BY num_transactions DESC
/