[TEST@myoracle] SQL>WITH T1 AS(
  2  SELECT 1001 callid,  3 dno,'1:00' starttime, '2:00' entime FROM DUAL UNION ALL
  3  SELECT 1001 callid,  1 dno,'2:00' starttime, '3:00' entime FROM DUAL UNION ALL
  4  SELECT 1001 callid,  2 dno,'3:00' starttime, '4:00' entime FROM DUAL UNION ALL
  5  SELECT 1001 callid,  1 dno,'4:00' starttime, '5:00' entime FROM DUAL UNION ALL
  6  SELECT 1001 callid,  1 dno,'5:00' starttime, '6:00' entime FROM DUAL UNION ALL
  7  SELECT 1001 callid,  1 dno,'6:00' starttime, '7:00' entime FROM DUAL UNION ALL
  8  SELECT 1001 callid,  2 dno,'7:00' starttime, '8:00' entime FROM DUAL UNION ALL
  9  SELECT 1002 callid,  1 dno,'2:20' starttime, '3:00' entime FROM DUAL
 10  )SELECT callid, dno, MIN(starttime) starttime, MAX(entime) entime
 11    FROM (SELECT callid,
 12                 dno,
 13                 starttime,
 14                 entime,
 15                 SUBSTR(starttime, 1, 1) - ROW_NUMBER() OVER(PARTITION BY callid, dno ORDER BY starttime) ROW_
 16            FROM T1)
 17   GROUP BY callid, dno, ROW_
 18   ORDER BY 1, 3
 19  ;

    CALLID        DNO STAR ENTI
---------- ---------- ---- ----
      1001          3 1:00 2:00
      1001          1 2:00 3:00
      1001          2 3:00 4:00
      1001          1 4:00 7:00
      1001          2 7:00 8:00
      1002          1 2:20 3:00

已选择6行。