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:
| Value | Geometry | Description |
|---|---|---|
| 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 intersect
TOUCH — the boundaries intersect but the interiors do not intersect
OVERLAPBDYDISJOINT — 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 intersect
EQUAL — the two objects have the same boundary and interior
CONTAINS — the interior and boundary of one object is completely contained in the interior of the other object
COVERS — the interior of one object is completely contained in the interior of the other object and their boundaries intersect
INSIDE — 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 |
