sql-server-2008 - LineString 查找通过我的 2 线的车辆（4 点）

Question

我有一个任务，我必须在 Google 地图（4 点）上绘制 2 条线，并且在提交事件中我需要显示通过这些点的车辆。我能够在谷歌地图上绘制 2 条线，这给了我 4 个纬度/经度格式的点。

现在的主要问题是如何查询数据库以使车辆通过两条线。我知道我可能必须在 T-SQL 中使用 LineString 函数，但我如何让所有车辆通过这些线路？欢迎任何建议。

Answer 1

鉴于我不确定您是如何表示您的“汽车”或您的“线条”并且必须做出假设，这个代码示例可能会为您提供帮助。它将返回一个数据集，指示哪些汽车已经通过了哪些线路。空间查询不是我的强项。也许其他人可以提供优化。

--  This is the first line as describer by 2 points
DECLARE @line1  GEOMETRY = geometry::STGeomFromText('LINESTRING(0 10, 10 10)', 0)
--  This is the second line as describer by another 2 points
DECLARE @line2  GEOMETRY = geometry::STGeomFromText('LINESTRING(0 20, 10 20)', 0)
--  @Car1's path is represented as a line that does NOT intersect the 2 defined lines above
DECLARE @Car1   GEOMETRY = geometry::STGeomFromText('LINESTRING(5 0, 5 11)', 0)
--  @Car2's path is represented as a line that DOES intersect that 2 defined lines above
DECLARE @Car2   GEOMETRY = geometry::STGeomFromText('LINESTRING(5 0, 5 23)', 0)

;WITH Lines (LineID, LineGeom) AS
(
    SELECT 1, @line1    UNION ALL
    SELECT 2, @line2
)
,Cars (CarID, CarGeom) AS
(
    SELECT 1, @Car1 UNION ALL
    SELECT 2, @Car2
)
SELECT   C.CarID
        ,L.LineID
FROM Cars   C
JOIN Lines  L ON L.LineGeom.STIntersects(C.CarGeom) = 1