通过 V$SESSION_LONGOPS 查看实时进度（最常用）

SELECT SID,
       SERIAL#,
       OPNAME,
       TO_CHAR(START_TIME, 'YYYY-MM-DD HH24:MI:SS') AS START_TIME,
       SOFAR,
       TOTALWORK,
       ROUND(SOFAR / TOTALWORK * 100, 2) AS "%_COMPLETE"
FROM   V$SESSION_LONGOPS
WHERE  OPNAME LIKE 'RMAN%'
AND    OPNAME NOT LIKE '%aggregate%'
AND    TOTALWORK <> 0
ORDER BY START_TIME ASC;