数据库函数 根据坐标经纬度计算距离算法

USE [KomtraxData]
GO
/****** Object:  UserDefinedFunction [dbo].[fnGetDistance]    Script Date: 2017/12/8 11:37:06 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER FUNCTION [dbo].[fnGetDistance](@LatBegin REAL, @LngBegin REAL, @LatEnd REAL, @LngEnd REAL) RETURNS FLOAT
  AS
BEGIN
  --距离(千米)
  DECLARE @Distance REAL
  DECLARE @EARTH_RADIUS REAL
  SET @EARTH_RADIUS = 6378.137  
  DECLARE @RadLatBegin REAL,@RadLatEnd REAL,@RadLatDiff REAL,@RadLngDiff REAL
  SET @RadLatBegin = @LatBegin *PI()/180.0  
  SET @RadLatEnd = @LatEnd *PI()/180.0  
  SET @RadLatDiff = @RadLatBegin - @RadLatEnd  
  SET @RadLngDiff = @LngBegin *PI()/180.0 - @LngEnd *PI()/180.0   
  SET @Distance = 2 *ASIN(SQRT(POWER(SIN(@RadLatDiff/2), 2)+COS(@RadLatBegin)*COS(@RadLatEnd)*POWER(SIN(@RadLngDiff/2), 2)))
  SET @Distance = @Distance * @EARTH_RADIUS  
  --SET @Distance = Round(@Distance * 10000) / 10000  
  RETURN @Distance
END

调用

select [dbo].[fnGetDistance](34, 114, 35, 115)

第一次创建alter 改为 create即可

数据库函数

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