如何在Sql UPDATE語句中添加TOP 1和PARTITION BY？

Question

我有以下SQL語句 - 它試圖找到所有我們的自行車道，相交郵編： -

UPDATE a 
SET a.ZipCodeId = d.ZipCodeId 
FROM [dbo].[BikePaths] a 
    INNER JOIN [dbo].[BikePathBoundaries] b ON b.ZipCodeId = c.ZipCodeId 
    INNER JOIN [dbo].[ZipCodeBoundaries] c ON b.Boundary.STIntersects(c.Boundary) = 1 

這很好......除非自行車路徑貫穿兩個或更多的郵編（其中一個發生很多）。所以，我想說，Get the zipcode which this bikepath MOSTLY intersects（我有另一個列表中其它地方所有bikpaths到郵編）。

如果這是一個SELECT statemement，它會是這個樣子......

SELECT a.BikePathId, a.BikePathName, c.ZipCodeId, d.ZipCode, 
    c.Boundary.STIntersection(d.Boundary).STArea() AS Area, 
    ROW_NUMBER() OVER (PARTITION BY a.BikePathId ORDER BY c.Boundary.STIntersection(d.Boundary).STArea() DESC) AS RowNumber 
FROM [dbo].[BikePaths] a 
    INNER JOIN [dbo].[BikePathBoundaries] b on a.BikePathId = b.BikePathId 
    INNER JOIN [dbo].[ZipCodeBoundaries] c on b.Boundary.STIntersects(c.Boundary) = 1 
    INNER JOIN [dbo].[ZipCodes] d on c.ZipCodeId = d.ZipCodeId 

，然後我可以再補充一個 TOP 1 WHERE RowNumber = 1，以確保我得到每BikePath一行..這將具有該自行車路徑主要包含在/相交中的郵政編碼。

我知道2nd Sql語句看起來很毛茸茸，加上了Geo-Spatial的東西..但是有人可以幫我將這個語句合併到UPDATE語句中嗎？

Answer 1

我不使用地理空間查詢，但不能把你的第二個查詢公用表表達式，並加入它在你的ROW_NUMBER場= 1？

;WITH CTE AS (
SELECT a.BikePathId, c.ZipCodeId, 
    Rnum =ROW_NUMBER() OVER (PARTITION BY a.BikePathId ORDER BY c.Boundary.STIntersection(d.Boundary)) 
FROM  [dbo].[BikePaths] a 
    INNER JOIN [dbo].[BikePathBoundaries] b on a.BikePathId = b.BikePathId 
    INNER JOIN [dbo].[ZipCodeBoundaries] c on b.Boundary.STIntersects(c.Boundary) = 1 
    INNER JOIN [dbo].[ZipCodes] d on c.ZipCodeId = d.ZipCodeId) 
UPDATE a 
SET a.ZipCodeId = cte.ZipCodeId 
FROM [dbo].[BikePaths] a 
    INNER JOIN cte on cte.bikepathid =a.bikepathid and cte.rnum=1;