Har*_*d W 4 sql sql-server sql-server-2008
我有一个多表并连接每个表.结果是这样的:
CarId CarLat CarLon Path Minute Distance
325 36.000 37.200 H4 74 250
344 36.050 37.040 H6 75 500
365 36.300 37.600 H4 76 750
311 36.060 37.080 H5 77 800
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如你所见,路径有2个H4,我想显示更小的分钟路径.像这样 :
CarId CarLat CarLon Path Minute Distance
325 36.000 37.200 H4 74 250
344 36.050 37.040 H6 75 500
311 36.060 37.080 H5 77 800
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我怎样才能做到这一点 ?
您可以使用SQL SERVER ROW_NUMBER来确定这一点.
所以像
;WITH Vals AS (
SELECT *,
ROW_NUMBER() (PARTITION BY Path ORDER BY Minute) RowID
FROM Table
)
SELECT *
FROM Vals
WHERE RowID = 1
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