Question

使用SQL Server 2014。

我正在尝试让SQL Server计算世界各地机场之间的距离，以公里，英里和航海里程为单位。大多数情况下，下面的方法有效，但当距离超过10,000公里时它似乎失败了（尽管这只是一个假设）。

    DECLARE @Radius_Km AS FLOAT
DECLARE @Radius_Mi AS FLOAT
DECLARE @Radius_Nm AS FLOAT
DECLARE @Pi AS FLOAT
DECLARE @D2R AS FLOAT

SET @Radius_Km = '6370.97327862'
SET @Radius_Mi = '3958.73926185'
SET @Radius_Nm = '3440.05036642'
SET @Pi = '3.14159265358979'
SET @D2R = @Pi / 180;


WITH RawData AS
(
    SELECT DISTINCT Sched.AirlineName, Sched.AirlineIATA, Sched.AirlineICAO, Sched.FlightNo,

            Sched.DepartureAirportName, Sched.DepartureAirportIATA, DepAprt.AirportICAO AS [DepartureAirportICAO], 

            DepAprt.Latitude AS [DepartureAirportLatitude], DepAprt.Longitude AS [DepartureAirportLongitude],

            Sched.ArrivalAirportName, Sched.ArrivalAirportIATA, ArrAprt.AirportICAO AS [ArrivalAirportICAO], 

            ArrAprt.Latitude AS [ArrivalAirportLatitude], ArrAprt.Longitude AS [ArrivalAirportLongitude]

    FROM VAS_Live.dbo.RawData_FR24 AS Sched

        LEFT JOIN VAS_Live.dbo.ReferenceData_Airports AS DepAprt
            ON Sched.DepartureAirportIATA = DepAprt.AirportIATA

        LEFT JOIN VAS_Live.dbo.ReferenceData_Airports AS ArrAprt
            ON Sched.ArrivalAirportIATA = ArrAprt.AirportIATA

),

RadianConvert AS
(
    SELECT *,

        ((DepartureAirportLatitude / 180) * @Pi) AS [DALat],
        ((DepartureAirportLongitude / 180) * @Pi) AS [DALon],
        ((ArrivalAirportLatitude / 180) * @Pi) AS [AALat],
        ((ArrivalAirportLongitude / 180) * @Pi) AS [AALon]

    FROM RawData
),

CentralSphericalAngle AS
(
    SELECT *,

    (Sin(DALat) * Sin(AALat)) + (Cos(DALat) * Cos(AALat) * Cos(AALon - DALon)) AS [Test]

    FROM RadianConvert
),

TestCTE AS
(
    SELECT *,

        @Radius_Mi * ATAN(SQRT(1 - POWER(Test, 2)) / Test) AS [Test2]

    FROM CentralSphericalAngle
)

SELECT *
FROM TestCTE
WHERE DepartureAirportIATA = 'LHR' AND ArrivalAirportIATA = 'SIN'

对于上面的例子，LHR Lat＆amp; Lon如下：

51.4775 -0.461389

SIN Lat＆amp;长期如下：

1.35019 103.994

我已经知道距离大致是：

公元 - 10,883

Mi - 6,762

Nm - 5,876

知道SQL为什么给我-5674？

我曾经使用VBA和Excel来计算这些数据，这是有效的。我注意到了抵达AALat＆amp;转换为Radians时DALon计算错误 - 但我不知道为什么。

由于

马修

Answer 1

从Lat＆amp ;;计算距离（英里）函数。 Lon as by：

CREATE FUNCTION [dbo].[getDistanceFromLatLon](@lat1  float, @lon1 float, @lat2 float, @lon2 float)   
Returns float   
AS  
BEGIN 
 Declare  @R  int  
    set @R= 6371;   

    Declare @a float  
    Declare  @c  float  
    Declare  @d  float  

    Declare @dLat float;  
    Declare @dLon float;  
    declare @DegToRad float
BEGIN

    set @DegToRad= (select PI() / 180)
    set @dLat = (@lat2 - @lat1)* @DegToRad;   
    set @dLon = (@lon2 - @lon1)* @DegToRad;  
    set @a =   sin(@dLat / 2) * sin(@dLat / 2) +  
   cos((@lat1)* @DegToRad) * cos((@lat2)* @DegToRad) *  
    sin(@dLon / 2) * sin(@dLon / 2) ;  
    set @c = 2 * atn2(sqrt(@a), sqrt(1 - @a));  
    set @d = @R * @c;   
 END  

     return (@d * 0.6214)

END

从这个功能，

DECLARE @Kilimiles float
DECLARE @miles float
DECLARE @nauticalmile float
SET @miles=(SELECT dbo.[getDistanceFromLatLon](51.4775, -0.461389,1.35019 ,103.994))
SET @Kilimiles=@miles * 1.60934
SET @nauticalmile= @miles * 0.868976

SELECT @miles as Mile,@Kilimiles as Kilomile,@nauticalmile as NauticalMile

SQL Server - 计算两个纬度之间的距离＆amp;经度的

1 个答案: