WITH tbl AS
(
SELECT 'A' cd, '차씨' nm, '2016.04.12' sdt, '2016.04.24' edt FROM dual
UNION ALL SELECT 'A', '김씨', '2016.05.12', ''           FROM dual
UNION ALL SELECT 'A', '이씨', '2016.06.12', '2016.06.19' FROM dual
UNION ALL SELECT 'A', '박씨', '2016.07.12', ''           FROM dual
UNION ALL SELECT 'A', '손씨', '2016.08.12', '2016.08.30' FROM dual
)
SELECT DISTINCT cd
  FROM tbl m
 WHERE sdt LIKE '2016.05'||'%'
   AND NOT EXISTS (SELECT 1
                     FROM tbl s
                    WHERE sdt < '2016.05'
                      AND NVL(edt, '9999.12.31') > '2016.05'
                      AND s.cd = m.cd
                   )
;

WITH TBL AS (

SELECT 'A' AGENT, 'CHA' NAME, '04.12' IN_DATE, '04.24' OUT_DATE FROM DUAL UNION ALL

SELECT 'A' AGENT, 'KIM' NAME, '05.12' IN_DATE, '' OUT_DATE FROM DUAL UNION ALL

SELECT 'A' AGENT, 'LEE' NAME, '06.12' IN_DATE, '06.19' OUT_DATE FROM DUAL UNION ALL

SELECT 'A' AGENT, 'PARK' NAME, '07.12' IN_DATE, '' OUT_DATE FROM DUAL UNION ALL

SELECT 'B' AGENT, 'PARK' NAME, '07.12' IN_DATE, '' OUT_DATE FROM DUAL UNION ALL

SELECT 'A' AGENT, 'SON' NAME, '08.12' IN_DATE, '08.30' OUT_DATE FROM DUAL

)

SELECT * FROM TBL A

WHERE NOT EXISTS (

SELECT 1 FROM TBL

WHERE ADD_MONTHS(TO_DATE('07.30', 'MM.DD'), -1) BETWEEN TO_DATE(IN_DATE, 'MM.DD') AND NVL(TO_DATE(OUT_DATE, 'MM.DD'), SYSDATE)

AND AGENT = A.AGENT

)

 감사합니다

원하는 결과를 얻었습니다