我有一个包含类别,日期和费率的表。每个类别在不同的日期可以有不同的费率,一个类别在给定的日期只能有一个费率。如何使用MySQL对连续范围进行分组
Id CatId Date Rate
------ ------ ------------ ---------
000001 12 2009-07-07 1
000002 12 2009-07-08 1
000003 12 2009-07-09 1
000004 12 2009-07-10 2
000005 12 2009-07-15 1
000006 12 2009-07-16 1
000007 13 2009-07-08 1
000008 13 2009-07-09 1
000009 14 2009-07-07 2
000010 14 2009-07-08 1
000010 14 2009-07-10 1
唯一索引(CATID,日期,价格) 我想对于每个类别组的所有连续日期范围,只保留开始和范围的结束。 对于前面的例子中,我们将有:
CatId Begin End Rate
------ ------------ ------------ ---------
12 2009-07-07 2009-07-09 1
12 2009-07-10 2009-07-10 2
12 2009-07-15 2009-07-16 1
13 2009-07-08 2009-07-09 1
14 2009-07-07 2009-07-07 2
14 2009-07-08 2009-07-08 1
14 2009-07-10 2009-07-10 1
我发现the forum类似的解决方案,它并没有完全放弃的结果
WITH q AS
(
SELECT *,
ROW_NUMBER() OVER (PARTITION BY CatId, Rate ORDER BY [Date]) AS rnd,
ROW_NUMBER() OVER (PARTITION BY CatId ORDER BY [Date]) AS rn
FROM my_table
)
SELECT CatId AS catidd, MIN([Date]) as beginn, MAX([Date])as endd, Rate
FROM q
GROUP BY CatId, rnd - rn, Rate
查阅SQL FIDDLE 我如何做同样的事情在MySQL ? 请帮忙!
为什么你的例子显示了'(CATID,率)=( 14,1)'当基础表中没有'2009-07-09'时,从'2009-07-08'到'2009-07-10'的结果范围? C.F. (CatId,Rate)=(12,1)',由于它的不连续性,它会产生两个结果范围。 – eggyal
感谢eggyal,现在它已更正 – Fouzi