sql里比较时间范围的方式

CREATE TABLE #Test
(
 createDate varchar(8)
)

INSERT INTO #Test
SELECT '20080602'
UNION ALL
SELECT '20080603'
UNION ALL
SELECT '20080701'

SELECT * FROM #Test

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SELECT * FROM #Test
WHERE CAST(createDate as datetime)
BETWEEN '20080604' AND '20080730'     [查询方式一]

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SELECT * FROM #Test1
WHERE cast(createDate as datetime)
BETWEEN '2008-06-04' AND '2008-07-30' [查询方式二：与方式一效果一样]

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SELECT * FROM #Test1
WHERE cast(createDate as datetime)
BETWEEN '2008/06/04' AND '2008/07/30' [查询方式三：与方式一，二效果同]

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