数据库函数

DECLARE @g geometry;

DECLARE @h geometry;空间数据库操作函数

1、STArea() 面积计算

2、STBuffer()缓冲区计算

3、STCrosses()如果geometry实例与另一个geometry实例相交，则返回1。否则，返回0

SET @g = geometry::STGeomFromText('LINESTRING(0 2, 2 0)', 0);

SET @h = geometry::STGeomFromText('LINESTRING(0 0, 2 2)', 0);

SELECT @g.STCrosses(@h);

4、STDifference()返回一个对象，该对象表示来自一个geometry实例的点，这些点在另一个geometry 实例中不存在

SET @g = geography::STGeomFromText('POL YGON((-122.358 47.653, -122.348 47.649, -122.348 47.658, -122.358 47.658, -122.358 47.653))', 4326);

SET @h = geography::STGeomFromText('LINESTRING(-122.360 47.656, -122.343 47.656)', 4326);

SELECT @g.STDifference(@h).ToString();

5、STDisjoint()如果一个geography 实例与另一个geography 实例在空间上不相联，则返回1。否则，返回0

SET @g = geography::STGeomFromText('LINESTRING(-122.360 47.656, -122.343 47.656)', 4326);

SET @h = geography::STGeomFromText('POINT(-122.34900 47.65100)', 4326);

SELECT @g.STDisjoint(@h)

6、STDistance()返回一个geometry 实例中的点与另一个geometry 实例中的点之间的最短距离

SET @g = geometry::STGeomFromText('POL YGON((0 0, 2 0, 2 2, 0 2, 0 0))', 0);

SET @h = geometry::STGeomFromText('POINT(10 10)', 0);

SELECT @g.STDistance(@h

7、STEnvelope()返回实例的最小轴对齐边界矩形

SET @g = geometry::STGeomFromText('LINESTRING(0 0, 2 3)', 0);

SELECT @g.STEnvelope().ToString()

8、STIntersection()返回一个对象，该对象表示一个Geometry 实例与另一个Geometry 实例的交点

SET @g = geography::STGeomFromText('POL YGON((-122.358 47.653, -122.348 47.649, -122.348 47.658, -122.358 47.658, -122.358 47.653))', 4326);

SET @h = geography::STGeomFromText('LINESTRING(-122.360 47.656, -122.343 47.656)', 4326);

SELECT @g.STIntersection(@h).ToString()

9、STIntersects()如果geography 实例与另一个geography 实例相交，则返回1。否则，返回0

SET @g = geometry::STGeomFromText('LINESTRING(0 2, 2 0, 4 2)', 0);

SET @h = geometry::STGeomFromText('POINT(1 1)', 0);

SELECT @g.STIntersects(@h)

10、STOverlaps()确定指定的Geometry 对象是否与当前Geometry 重叠

SET @g = geography::Parse('POL YGON ((-120.533 46.566, -118.283 46.1, -122.3 47.45, -120.533 46.566))');

SET @h= geography::Parse('POL YGON ((-120.533 46.566, -118.283 46.1, -122.3 47.45, -120.533 46.566))')

SELECT @g.STOverlaps(@h)

11/STSymDifference()返回表示位于一个geometry 实例或者另一个geometry 实例中的所有点的对象，但不包含同时位于这两个实例中的那些点

SET @g = geometry::STGeomFromText('POL YGON((0 0, 0 2, 2 2, 2 0, 0 0))', 0);

SET @h = geometry::STGeomFromText('POL YGON((1 1, 3 1, 3 3, 1 3, 1 1))', 0);

SELECT @g.STSymDifference(@h).ToString()

12、STTouches()是否接触

SET @g = geometry::STGeomFromText('LINESTRING(0 2, 2 0, 4 2)', 0);

SET @h = geometry::STGeomFromText('POINT(1 1)', 0);

SELECT @g.STTouches(@h)

13、@pg.STWithin(@s)@pg是否包含在@s里

SET @g = geometry::STGeomFromText('POL YGON((0 0, 2 0, 2 2, 0 2, 0 0))', 0);

SET @h = geometry::STGeomFromText('POL YGON((1 1, 3 1, 3 3, 1 3, 1 1))', 0);

SELECT @g.STWithin(@h)

14、STGeometryN（geometry 数据类型）返回geometry collection 中的指定几何图形

SET @cd=geometry::STGeomFromText('MULTIPOINT((30.6666587469201

104.062021177233),(29.5076372217973106.489384971208))',4326)

Select STGeometryN（1）.STAsText() 表示返回第一个点

15、STIsValid();验证geometry对象是否为正确的空间对象，若正确，返回1，否则0

SET @g=geometry::STGeomFromText('MULTILINESTRING((30.6666 104.06202,

29.50763 106.48938),(30.6666 104.06202,33.78142 105.97914))',4326);

select @g.STIsValid()