Oracle Spatial中SDO_GEOMETRY类型：
CREATE TYPE SDO_GEOMETRY AS OBJECT(
SDO_GTYPE NUMBER,--几何类型，如点线面
SDO_SRID NUMBER,--几何的空间参考坐标系
SDO_POINT SDO_POINT_TYPE,--如果几何为点类型，则存储点坐标，否则为空
SDO_ELEM_INFO SDO_ELEM_INFO_ARRAY,--定义如何理解SDO_ORDINATES中的坐标序列
SDO_ORDINATES SDO_ORDINATE_ARRAY--存储实际坐标，以X,Y以及不同点之间以逗号隔开
)
两个对象之间关系：
RELATE
SDO_GEOM.RELATE --确定两个对象的交互方式
eg:
SDO_GEOM.RELATE(geom1 IN SDO_GEOMETRY,dim1 IN SDO_DIM_ARRAY,mask IN VARCHAR2, geom2 IN SDO_GEOMETRY,dim2 IN SDO_DIM_ARRAY) RETURN VARCHAR2;
SDO_GEOM.RELATE(geom1 IN SDO_GEOMETRY,mask IN VARCHAR2,geom2 IN SDO_GEOMETRY, tol IN NUMBER)RETURN VARCHAR2;--tol容许的精度范围
mask:
ANYINTERACT:geom2落在geom1面上，包括边上
CONTAINS:geom2完全包含在geom1几何对象中，并且两个几何对象的边没有交叉
COVEREDBY:geom1完全包含在geom2中，并且两个几何对象的边有一个或多个点相互重叠
COVERS:geom2完全包含在geom1中，并且两个几何对象的边有一个或多个点相互重叠
DISJOINT:两个几何没有重叠交叉点，也没有共同的边
EQUAL:两个几何相等
INSIDE:geom1完全包含在geom2几何对象中，并且两个几何对象的边没有交叉
ON:geom1的边和内部的线完全在geom2上
OVERLAPBDYDISJOINT:两个几何对象交迭，但是边没有交叉
OVERLAPBDYINTERSECT:两个几何对象叫迭，并且边有部分交叉
TOUCH:两个结合对象有共同的边，但没有交叉
WITHIN_DISTANCE
SDO_GEOM.WITHIN_DISTANCE --确定两个几何是否在彼此指定的距离之内
eg:
SDO_GEOM.WITHIN_DISTANCE(geom1 IN SDO_GEOMETRY,dim1 IN SDO_DIM_ARRAY,dist IN NUMBER, geom2 IN SDO_GEOMETRY,dim2 IN SDO_DIM_ARRAY[, units IN VARCHAR2]) RETURN VARCHAR2;
SDO_GEOM.WITHIN_DISTANCE(geom1 IN SDO_GEOMETRY,dist IN NUMBER,geom2 IN SDO_GEOMETRY,tol IN NUMBER[, units IN VARCHAR2]) RETURN VARCHAR2;
验证：
VALIDATE_GEOMETRY_WITH_CONTEXT
SDO_GEOM.VALIDATE_GEOMETRY_WITH_CONTEXT --确定几何是否有效，如果几何无效，则返回上下文信息
eg:
SDO_GEOM.VALIDATE_GEOMETRY_WITH_CONTEXT(theGeometry IN SDO_GEOMETRY, theDimInfo IN SDO_DIM_ARRAY,conditional IN VARCHAR2 DEFAULT 'TRUE') RETURN VARCHAR2;
SDO_GEOM.VALIDATE_GEOMETRY_WITH_CONTEXT(theGeometry IN SDO_GEOMETRY,tolerance IN NUMBER,conditional IN VARCHAR2 DEFAULT 'TRUE') RETURN VARCHAR2;
VALIDATE_LAYER_WITH_CONTEXT
SDO_GEOM.VALIDATE_LAYER_WITH_CONTEXT --确定存储在列中的所有几何是否有效，并返回有关任何无效几何的上下文信息
eg:
SDO_GEOM.VALIDATE_LAYER_WITH_CONTEXT(geom_table IN VARCHAR2,geom_column IN VARCHAR2,result_table IN VARCHAR2,commit_interval IN NUMBER DEFAULT -1,conditional IN VARCHAR2 DEFAULT 'TRUE');
单对象操作：
SDO_ARC_DENSIFY
SDO_GEOM.SDO_ARC_DENSIFY --简化，将圆弧简化成由直线组成的近似多段线；将圆近似成N多边形
eg:
SDO_GEOM.SDO_ARC_DENSIFY(geom IN SDO_GEOMETRY,dim IN SDO_DIM_ARRAY, params IN VARCHAR2) RETURN SDO_GEOMETRY;
SDO_GEOM.SDO_ARC_DENSIFY(geom IN SDO_GEOMETRY,tol IN NUMBER, params IN VARCHAR2) RETURN SDO_GEOMETRY;
SDO_AREA
SDO_GEOM.SDO_AREA --计算多边形的面积
eg:
SDO_GEOM.SDO_AREA(geom IN SDO_GEOMETRY,dim IN SDO_DIM_ARRAY [, unit IN VARCHAR2]) RETURN NUMBER;
SDO_GEOM.SDO_AREA(geom IN SDO_GEOMETRY,tol IN NUMBER [, unit IN VARCHAR2]) RETURN NUMBER;
SDO_BUFFER
SDO_GEOM.SDO_BUFFER --在几何体外部或内部生成缓冲区
eg:
SDO_GEOM.SDO_BUFFER(geom IN SDO_GEOMETRY,dim IN SDO_DIM_ARRAY,dist IN NUMBER[, params IN VARCHAR2]) RETURN SDO_GEOMETRY;
SDO_GEOM.SDO_BUFFER(geom IN SDO_GEOMETRY,dist IN NUMBER,tol IN NUMBER[, params IN VARCHAR2]) RETURN SDO_GEOMETRY;
SDO_CENTROID
SDO_GEOM.SDO_CENTROID --计算多边形的质心
eg:
SDO_GEOM.SDO_CENTROID(geom1 IN SDO_GEOMETRY,dim1 IN SDO_DIM_ARRAY) RETURN SDO_GEOMETRY;
SDO_GEOM.SDO_CENTROID(geom1 IN SDO_GEOMETRY,tol IN NUMBER) RETURN SDO_GEOMETRY;
SDO_CONVEXHULL
SDO_GEOM.SDO_CONVEXHULL --返回几何对象的凸包的多边形类型对象
eg:
SDO_GEOM.SDO_CONVEXHULL(geom1 IN SDO_GEOMETRY,dim1 IN SDO_DIM_ARRAY) RETURN SDO_GEOMETRY;
SDO_GEOM.SDO_CONVEXHULL(geom1 IN SDO_GEOMETRY, tol IN NUMBER) RETURN SDO_GEOMETRY;
SDO_LENGTH
SDO_GEOM.SDO_LENGTH --计算几何的长度或周长
eg:
SDO_GEOM.SDO_LENGTH(geom IN SDO_GEOMETRY,dim IN SDO_DIM_ARRAY[, unit IN VARCHAR2][, count_shared_edges IN NUMBER]) RETURN NUMBER;
SDO_GEOM.SDO_LENGTH(geom IN SDO_GEOMETRY,tol IN NUMBER[, unit IN VARCHAR2] [, count_shared_edges IN NUMBER]) RETURN NUMBER;
SDO_MAX_MBR_ORDINATE
SDO_GEOM.SDO_MAX_MBR_ORDINATE --返回几何对象最小边界矩形的指定纵坐标的最大值
eg:
SDO_GEOM.SDO_MAX_MBR_ORDINATE(geom IN SDO_GEOMETRY,ordinate_pos IN NUMBER) RETURN NUMBER;
SDO_GEOM.SDO_MAX_MBR_ORDINATE(geom IN SDO_GEOMETRY,dim IN SDO_DIM_ARRAY,ordinate_pos IN NUMBER) RETURN NUMBER;
SDO_MIN_MBR_ORDINATE
SDO_GEOM.SDO_MIN_MBR_ORDINATE --返回几何对象最小边界矩形的指定纵坐标的最小值
eg:
SDO_GEOM.SDO_MIN_MBR_ORDINATE(geom IN SDO_GEOMETRY,ordinate_pos IN NUMBER ) RETURN NUMBER;
SDO_GEOM.SDO_MIN_MBR_ORDINATE(geom IN SDO_GEOMETRY,dim IN SDO_DIM_ARRAY,ordinate_pos IN NUMBER) RETURN NUMBER;
SDO_MBR
SDO_GEOM.SDO_MBR --返回几何对象最小边界矩形
eg:
SDO_GEOM.SDO_MBR(geom IN SDO_GEOMETRY[, dim IN SDO_DIM_ARRAY]) RETURN SDO_GEOMETRY;
SDO_POINTONSURFACE
SDO_GEOM.SDO_POINTONSURFACE --返回一个保证在多边形表面上的点
eg:
SDO_GEOM.SDO_POINTONSURFACE(geom1 IN SDO_GEOMETRY,dim1 IN SDO_DIM_ARRAY) RETURN SDO_GEOMETRY;
SDO_GEOM.SDO_POINTONSURFACE(geom1 IN SDO_GEOMETRY,tol IN NUMBER) RETURN SDO_GEOMETRY;
SDO_VOLUME
SDO_GEOM.SDO_VOLUME --计算三维立体几何体的体积
eg:
SDO_GEOM.SDO_VOLUME(geom IN SDO_GEOMETRY,tol IN NUMBER[, unit IN VARCHAR2]) RETURN NUMBER;
双目标操作：
SDO_CLOSEST_POINTS
SDO_GEOM.SDO_CLOSEST_POINTS --计算两个几何之间的最小距离，并返回距离最小时在几何上的两点
eg:
SDO_GEOM.SDO_CLOSEST_POINTS(geom1 IN SDO_GEOMETRY,geom2 IN SDO_GEOMETRY,tolerance IN NUMBER,unit IN VARCHAR2,dist OUT NUMBER,geoma OUT SDO_GEOMETRY,geomb OUT SDO_GEOMETRY);
SDO_DISTANCE
SDO_GEOM.SDO_DISTANCE --计算两个几何对象之间的距离
eg:
SDO_GEOM.SDO_DISTANCE(geom1 IN SDO_GEOMETRY,dim1 IN SDO_DIM_ARRAY,geom2 IN SDO_GEOMETRY,dim2 IN SDO_DIM_ARRAY[, unit IN VARCHAR2]) RETURN NUMBER;
SDO_GEOM.SDO_DISTANCE(geom1 IN SDO_GEOMETRY,geom2 IN SDO_GEOMETRY,tol IN NUMBER [, unit IN VARCHAR2]) RETURN NUMBER;
SDO_DIFFERENCE
SDO_GEOM.SDO_DIFFERENCE --返回几何对象（两个几何对象的拓扑差异，MINUS操作）
eg:
SDO_GEOM.SDO_DIFFERENCE(geom1 IN SDO_GEOMETRY,dim1 IN SDO_DIM_ARRAY,geom2 IN SDO_GEOMETRY,dim2 IN SDO_DIM_ARRAY) RETURN SDO_GEOMETRY;
SDO_GEOM.SDO_DIFFERENCE(geom1 IN SDO_GEOMETRY,geom2 IN SDO_GEOMETRY, tol IN NUMBER) RETURN SDO_GEOMETRY;
SDO_INTERSECTION
SDO_GEOM.SDO_INTERSECTION --返回几何对象（两个几何对象的拓扑交点，AND操作）
eg:
SDO_GEOM.SDO_INTERSECTION(geom1 IN SDO_GEOMETRY,dim1 IN SDO_DIM_ARRAY,geom2 IN SDO_GEOMETRY,dim2 IN SDO_DIM_ARRAY) RETURN SDO_GEOMETRY;
SDO_GEOM.SDO_INTERSECTION(geom1 IN SDO_GEOMETRY,geom2 IN SDO_GEOMETRY, tol IN NUMBER) RETURN SDO_GEOMETRY;
SDO_UNION
SDO_GEOM.SDO_UNION --返回几何对象（两个几何对象的拓扑结合，OR操作）
eg:
SDO_GEOM.SDO_UNION(geom1 IN SDO_GEOMETRY,dim1 IN SDO_DIM_ARRAY, geom2 IN SDO_GEOMETRY,dim2 IN SDO_DIM_ARRAY) RETURN SDO_GEOMETRY;
SDO_GEOM.SDO_UNION(geom1 IN SDO_GEOMETRY,geom2 IN SDO_GEOMETRY, tol IN NUMBER ) RETURN SDO_GEOMETRY;
SDO_XOR
SDO_GEOM.SDO_XOR --返回几何对象（两个几何对象的拓扑对称差异，XOR操作）
eg:
SDO_GEOM.SDO_XOR(geom1 IN SDO_XOR,dim1 IN SDO_DIM_ARRAY,geom2 IN SDO_GEOMETRY,dim2 IN SDO_DIM_ARRAY) RETURN SDO_GEOMETRY;
SDO_GEOM.SDO_XOR(geom1 IN SDO_GEOMETRY,geom2 IN SDO_GEOMETRY, tol IN NUMBER ) RETURN SDO_GEOMETRY;
实例：
--wkt转geometry
select sdo_geometry(TO_CHAR(SDO_GEOMETRY(2003, NULL, NULL, SDO_ELEM_INFO_ARRAY(1, 1003, 1), SDO_ORDINATE_ARRAY(5, 5, 5, 7, 1, 7, 1, 1, 5, 1, 5, 3, 6, 3, 6, 5, 5, 5)).get_wkt())) from dual
--wkt转geometry
select SDO_UTIL.from_wktgeometry(TO_CHAR(SDO_GEOMETRY(2003, NULL, NULL, SDO_ELEM_INFO_ARRAY(1, 1003, 1), SDO_ORDINATE_ARRAY(5, 5, 5, 7, 1, 7, 1, 1, 5, 1, 5, 3, 6, 3, 6, 5, 5, 5)).get_wkt())) from dual
--geometry转wkt
select TO_CHAR(SDO_GEOMETRY(2003, NULL, NULL, SDO_ELEM_INFO_ARRAY(1, 1003, 1), SDO_ORDINATE_ARRAY(5, 5, 5, 7, 1, 7, 1, 1, 5, 1, 5, 3, 6, 3, 6, 5, 5, 5)).get_wkt()) from dual
--geometry转wkt
select SDO_UTIL.to_wktgeometry_varchar(SDO_GEOMETRY(2003, NULL, NULL, SDO_ELEM_INFO_ARRAY(1, 1003, 1), SDO_ORDINATE_ARRAY(5, 5, 5, 7, 1, 7, 1, 1, 5, 1, 5, 3, 6, 3, 6, 5, 5, 5))) from dual
--geometry转wkt（不受oracle字段只能少于4000个字符长度影响）
select SDO_UTIL.to_wktgeometry(SDO_GEOMETRY(2003, NULL, NULL, SDO_ELEM_INFO_ARRAY(1, 1003, 1), SDO_ORDINATE_ARRAY(5, 5, 5, 7, 1, 7, 1, 1, 5, 1, 5, 3, 6, 3, 6, 5, 5, 5))) from dual
--合并
select SDO_GEOM.SDO_UNION(SDO_GEOMETRY('POLYGON((1 1,5 1,5 5,1 5,1 1))'),SDO_GEOMETRY('POLYGON((2 2,2 3,3 3,3 2,2 2))'),0.001 ) from dual;
--缓冲区
select SDO_UTIL.to_wktgeometry_varchar(SDO_GEOM.SDO_BUFFER(SDO_GEOMETRY('POLYGON((1 1,5 1,5 5,1 5,1 1))'),1000,0.01)) from dual;
--点在面内
select SDO_GEOM.RELATE(SDO_GEOMETRY('POLYGON((1 1,5 1,5 5,1 5,1 1))'),'CONTAINS',SDO_GEOMETRY('POINT(12 2)'), 0.01) from dual;
--对象相交
select SDO_GEOM.RELATE(SDO_GEOMETRY('POLYGON((0 0,0 1,1 1,1 0,0 0))'),'ANYINTERACT',SDO_GEOMETRY('POLYGON((0.5 0.5,0.5 1.5,1.5 1.5,1.5 0.5,0.5 0.5))'), 0.01) from dual;