ArcMap

ST_Entity

定义

ST_Entity 返回几何对象的空间实体类型。空间实体类型是存储在几何对象的实体成员字段中的值。

语法

Oracle 和 PostgreSQL

sde.st_entity (geometry1 sde.st_geometry)

SQLite

st_entity (geometry1 geometryblob)

返回类型

将返回数字 (Oracle) 或整数（SQLite 和 PostgreSQL）来表示以下实体类型：

0

nil 形状

1

点

2

线（包括 spaghetti 线）

4

线串

8

面/区域

257

多点

258

多线（包括 spaghetti 线）

260

多线串

264

多区域

示例

以下示例会创建一个表并向表中插入不同的几何。ST_Entity 随即在表上运行并返回表中各记录的几何子类型。

Oracle

CREATE TABLE sample_geos (
 id integer,
 geometry sde.st_geometry
);
INSERT INTO sample_geos (id, geometry) VALUES (
 1901,
 sde.st_geometry ('point (1 2)', 4326)
);
INSERT INTO sample_geos (id, geometry) VALUES (
 1902,
 sde.st_geometry ('linestring (33 2, 34 3, 35 6)', 4326)
);
INSERT INTO sample_geos (id, geometry) VALUES (
 1903,
 sde.st_geometry ('polygon ((3 3, 4 6, 5 3, 3 3))', 4326)
);
SELECT sde.st_entity (geometry) entity, UPPER (sde.st_geometrytype (geometry)) TYPE
 FROM sample_geos;

SELECT 语句返回以下值：

 ENTITY        TYPE
    1    ST_POINT
    4    ST_LINESTRING
    8    ST_POLYGON

PostgreSQL

CREATE TABLE sample_geos (
 id integer,
 geometry sde.st_geometry
);
INSERT INTO sample_geos (id, geometry) VALUES (
 1900,
 sde.st_geometry ('Point Empty', 4326)
);
INSERT INTO sample_geos (id, geometry) VALUES (
 1901,
 sde.st_geometry ('point (1 2)', 4326)
);
INSERT INTO sample_geos (id, geometry) VALUES (
 1902,
 sde.st_geometry ('linestring (33 2, 34 3, 35 6)', 4326)
);
INSERT INTO sample_geos (id, geometry) VALUES (
 1903,
 sde.st_geometry ('polygon ((3 3, 4 6, 5 3, 3 3))', 4326)
);
INSERT INTO sde.entity_test (id, geometry) VALUES (
 1904,
 sde.st_geometry ('multipoint (10.01 20.03, 10.52 40.11, 30.29 41.56, 31.78 10.74)', 4326)
);
INSERT INTO sde.entity_test (id, geometry) VALUES (
 1905, 
 sde.st_geometry ('multilinestring ((10.01 20.03, 10.52 40.11, 30.29 41.56,31.78 10.74), (20.93 20.81, 21.52 40.10))', 4326)
);
INSERT INTO sde.entity_test (id, geometry) VALUES (
 1906, 
 sde.st_geometry ('multipolygon (((3 3, 4 6, 5 3, 3 3), (8 24, 9 25, 1 28, 8 24), (13 33, 7 36, 1 40, 10 43, 13 33)))', 4326)
);
SELECT id AS "id",
 sde.st_entity (geometry) AS "entity",
 sde.st_geometrytype (geometry) AS "geom_type"
 FROM sample_geos;

SELECT 语句返回以下值：

 id       entity     geom_type
    1900     0          "ST_GEOMETRY"
    1901     1          "ST_POINT"
    1902     4          "ST_LINESTRING"
    1903     8          "ST_POLYGON"
    1904     257        "ST_MULTIPOINT"
    1905     260        "ST_MULTILINESTRING"
    1906     264        "ST_MULTIPOLYGON"

SQLite

CREATE TABLE sample_geos (
 id integer primary key autoincrement not null
);
SELECT AddGeometryColumn (
 NULL,
 'sample_geos',
 'geometry',
 4326,
 'geometry',
 'xy',
 'null'
);
INSERT INTO sample_geos (geometry) VALUES (
 st_geometry ('point (1 2)', 4326)
);
INSERT INTO sample_geos (geometry) VALUES (
 st_geometry ('linestring (33 2, 34 3, 35 6)', 4326)
);
INSERT INTO sample_geos (geometry) VALUES (
 st_geometry ('polygon ((3 3, 4 6, 5 3, 3 3))', 4326)
);
SELECT st_entity (geometry) AS "entity",
 st_geometrytype (geometry) AS "type"
 FROM sample_geos;

SELECT 语句返回以下值：

entity    type
1         ST_POINT
4         ST_LINESTRING
8         ST_POLYGON

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