SELECT  'A' AS KEY1,
        '20110505' AS COL1,
        '20110507' AS COL2
FROM    DUAL
UNION ALL
SELECT 'B' AS KEY2,
        '20110504' AS COL1,
        '20110506' AS COL2
FROM    DUAL

위와같은 한건을

다음과 같은 여러건으로 만들고 싶습니다.
날짜에 한계가 없으므로 하드코딩 방식은 안되구요.
좋은방법 있으신분 한 수 가르쳐 주세요.
 

SELECT 'A' AS KEY1, '20110505' AS COL1
FROM DUAL
UNION ALL
SELECT 'A' AS KEY1, '20110506' AS COL1
FROM DUAL
UNION ALL
SELECT 'A' AS KEY1, '20110507' AS COL1
FROM DUAL
UNION ALL
SELECT 'B' AS KEY1, '20110504' AS COL1
FROM DUAL
UNION ALL
SELECT 'B' AS KEY1, '20110505' AS COL1
FROM DUAL
UNION ALL
SELECT 'B' AS KEY1, '20110506' AS COL1
FROM DUAL