这么难得题目都不给点分!试试把,看可不可以! SELECT count(*), CASE FLOOR((TO_CHAR(DTIME,'MI'))/15) WHEN 0 THEN TO_CHAR(DTIME,'YYYYMMDDHH')||'0000' WHEN 1 THEN TO_CHAR(DTIME,'YYYYMMDDHH')||'1500' WHEN 2 THEN TO_CHAR(DTIME,'YYYYMMDDHH')||'3000' WHEN 3 THEN TO_CHAR(DTIME,'YYYYMMDDHH')||'4500' END as D_TIME FROM TABLE GROUP BY D_TIME