Oracle Spatial详解
Step1. 创建一张表，其中shape用来存放空间数据 CREATE TABLE mylake ( feature_id NUMBER PRIMARY KEY, name VARCHAR2(32), shape MDSYS.SDO_GEOMETRY);
Step2. 在user_sdo_geom_metadata 表中插入新记录，用于描述空间字段 INSERT INTO user_sdo_geom_metadata VALUES ( 'mylake',//---表名 'shape',//---字段名 MDSYS.SDO_DIM_ARRAY( MDSYS.SDO_DIM_ELEMENT('X', 0, 100, 0.05),//---X维最小，最大值和容忍度。 MDSYS.SDO_DIM_ELEMENT('Y', 0, 100, 0.05)//---Y维最小，最大值和容忍度 ), NULL//---坐标系，缺省为笛卡尔坐标系 );
Step3. 创建空间索引 CREATE INDEX mylake_idx ON mylake(shape) INDEXTYPE IS MDSYS.SPATIAL_INDEX
Step4. 插入空间数据 Oracle Spatial用MDSYS.SDO_GEOMETRY来存储空间数据,定义为：CREATE TYPE sdo_geometry AS OBJECT ( SDO_GTYPE NUMBER, SDO_SRID NUMBER, SDO_POINT SDO_POINT_TYPE, SDO_ELEM_INFO MDSYS.SDO_ELEM_INFO_ARRAY, SDO_ORDINATES MDSYS.SDO_ORDINATE_ARRAY); SDO_GTYPE：用四个数字定义了所有的形状 第一位:维数 第二位:线性表示。用于3，4维数据，二维为0 最后两位:
| 00 | UNKNOWN_GEOMETRY |
Spatial ignores this value |
| 01 | POINT |
A single point element |
| 02 | LINE or CURVE |
Contains one line string element that may be linear, curved or both |
| 03 | POLYGON |
Contains one polygon element with or without other polygon elements in it |
| 04 | COLLECTION |
A heterogeneous collection of elements |
| 05 | MULTIPOINT |
Contains one or more points |
| 06 | MULTILINE or MULTICURVE |
Contains one or more line string elements |
| 07 | MULTIPOLYGON |
Contains multiple polygon elements that maybe disjoint |
SDO_SRID：坐标系，NULL为笛卡尔坐标系。 SDO_POINT：Oracle Spatial也可定义单个的点，SDO_POINT的定义:CREATE TYPE sdo_point_type AS OBJECT (X NUMBER,Y NUMBER,Z NUMBER); 如果是二维，Z为NULL。 SDO_ELEM_INFO：每三个值描述一个元素。 第一个值：第一个顶点在SDO_ORDINATES_ARR开始位置 第二个值：元素类型 第三个值：顶点连接方式：1-通过直线连接，2-通过圆弧连接 定义为 CREATE TYPE sdo_elem_info_array AS VARRAY (1048576) of NUMBER; SDO_ORDINATES：几何图形所有顶点列表。定义为 CREATE TYPE sdo_ordinate_array AS VARRAY (1048576) of NUMBER;
FONT color=#003366>// 插入包含一个岛屿的湖泊INSERT INTO mylake VALUES( 10, 'Lake Calhoun', MDSYS.SDO_GEOMETRY( 2003, NULL, NULL, MDSYS.SDO_ELEM_INFO_ARRAY(1,1003,1, 19,2003,1), MDSYS.SDO_ORDINATE_ARRAY(0,0, 10,0, 10,10, 0,10, 0,0, 4,4, 6,4, 6,6, 4,6, 4,4) ));
// 插入两艘小船INSERT INTO mylake VALUES( 11, 'The Windswept', MDSYS.SDO_GEOMETRY( 2003, NULL, NULL, MDSYS.SDO_ELEM_INFO_ARRAY(1,1003,1), MDSYS.SDO_ORDINATE_ARRAY(2,2, 3,2, 3,2, 2,3, 2,2) ) ); INSERT INTO mylake VALUES( 12, 'Blue Crest', MDSYS.SDO_GEOMETRY( 2003, NULL, NULL, MDSYS.SDO_ELEM_INFO_ARRAY(1,1003,1), MDSYS.SDO_ORDINATE_ARRAY(7,7, 8,7, 8,7, 7,8, 7,7) ) );
Step4. 查询 Oracle Spatial查询数据包括二个处理过程： 1.只通过索引查询候选项。通过函数SDO_FILTER实现：SDO_FILTER(geometry1 MDSYS.SDO_GEOMETRY,geometry2 MDSYS.SDO_GEOMETRY, params VARCHAR2) geometry1：必须是被索引的几何数据 geometry2：不一定是表中的空间字段，也不要求被索引 params：Filter类型querytype=WINDOW：geometry2不要求来自表 querytype=JOIN：geometry2必须来自表
SELECT name boat_name FROM mylake t WHERE feature_id = 12 AND SDO_FILTER(t.shape, mdsys.sdo_geometry(2003,NULL,NULL, mdsys.sdo_elem_info_array(1,1003,1), mdsys.sdo_ordinate_array(2,2, 5,2, 5,5, 2,5, 2,2)), 'querytype=WINDOW') = 'TRUE'; 2.再检查每个候选项是否和条件精确匹配。通过函数SDO_RELATE实现： SDO_RELATE(geometry1 MDSYS.SDO_GEOMETRY, geometry2 MDSYS.SDO_GEOMETRY, params VARCHAR2) params：masktype类型
DISJOINT — the boundaries and interiors do not intersectTOUCH — the boundaries intersect but the interiors do not intersectOVERLAPBDYDISJOINT — the interior of one object intersects the boundary and interior of the other object, but the two boundaries do not intersect. This relationship occurs, for example, when a line originates outside a polygon and ends inside that polygon.OVERLAPBDYINTERSECT — the boundaries and interiors of the two objects intersectEQUAL — the two objects have the same boundary and interiorCONTAINS — the interior and boundary of one object is completely contained in the interior of the other objectCOVERS — the interior of one object is completely contained in the interior of the other object and their boundaries intersectINSIDE — the opposite of CONTAINS. A INSIDE B implies B CONTAINS A.COVEREDBY — the opposite of COVERS. A COVEREDBY B implies B COVERS A.ON — the interior and boundary of one object is on the boundary of the other object (and the second object covers the first object). This relationship occurs, for example, when a line is on the boundary of a polygon.ANYINTERACT — the objects are non-disjoint. // 选择在定义矩形内的所有小船 SELECT name boat_name FROM mylake t WHERE feature_id = 12 AND SDO_FILTER(t.shape, mdsys.sdo_geometry(2003,NULL,NULL, mdsys.sdo_elem_info_array(1,1003,1), mdsys.sdo_ordinate_array(2,2, 5,2, 5,5, 2,5, 2,2)), 'querytype=WINDOW') = 'TRUE' AND SDO_RELATE(t.shape, mdsys.sdo_geometry(2003,NULL,NULL, mdsys.sdo_elem_info_array(1,1003,1), mdsys.sdo_ordinate_array(2,2, 5,2, 5,5, 2,5, 2,2)), 'masktype=INSIDE querytype=WINDOW') = 'TRUE'
// masktype可联合使用SELECT feature_id id FROM mylake t WHERE feature_id = 12 AND SDO_FILTER(t.shape, mdsys.sdo_geometry(2003,NULL,NULL, mdsys.sdo_elem_info_array(1,1003,1), mdsys.sdo_ordinate_array(2,2, 5,2, 5,5, 2,5, 2,2)), 'querytype=WINDOW') = 'TRUE' AND SDO_RELATE(t.shape, mdsys.sdo_geometry(2003,NULL,NULL, mdsys.sdo_elem_info_array(1,1003,1), mdsys.sdo_ordinate_array(2,2, 5,2, 5,5, 2,5, 2,2)), 'masktype=INSIDE+TOUCH querytype=WINDOW') = 'TRUE'
Oracle Spatial 提供的其他查询函数：
| Query | Description |
SDO_NN |
Nearest neighbor |
SDO_SDO_WITHIN_DISTANCE |
All geometries with a certain distance |
| Functions | Description |
SDO_GEOM.SDO_MBR |
The minimum bounding rectangle for a geometry |
SDO_GEOM.SDO_DISTANCE |
The distance between two geometries |
SDO_GEOM.SDO_INTERSECTION |
Provides the intersection point of two geometries |
OracleSpatial初探http://blog.sina.com.cn/s/blog_439d2cef01009c4a.html
http://www.oracle.com/technology/products/spatial/htdocs/data_sheet_9i/9iR2_spatial_ds.html