ST_CoordDim

定义

ST_CoordDim 返回几何列的坐标值维度。

语法

Oracle 和 PostgreSQL

sde.st_coorddim (geometry1 sde.st_geometry)

SQLite

st_coorddim (geometry1 geometryblob)

返回类型

整型

2 = x,y 坐标

3 = x,y,z 或 x,y,m 坐标

4 = x,y,z,m 坐标

示例

在这些示例中，将创建包含 geotype 和 g1 两列的 coorddim_test 表。geotype 列存储 g1 几何列中存储的几何子类和维度的名称。

SELECT 语句列出 geotype 列中所存储的子类名称以及相应几何的坐标维度。

Oracle

--Create test table.
CREATE TABLE coorddim_test (
 geotype varchar(20),
 g1 sde.st_geometry
);

--Insert values to the test table.
INSERT INTO COORDDIM_TEST VALUES (
 'Point',
 sde.st_geometry ('point (60.567222 -140.404)', 4326)
);

INSERT INTO COORDDIM_TEST VALUES (
 'Point Z',
 sde.st_geometry ('point Z (60.567222 -140.404 5959)', 4326)
);

INSERT INTO COORDDIM_TEST VALUES (
 'Point M',
 sde.st_geometry ('point M (60.567222 -140.404 5250)', 4326)
);

INSERT INTO COORDDIM_TEST VALUES (
 'Point ZM',
 sde.st_geometry ('point ZM (60.567222 -140.404 5959 5250)', 4326)
);

--Determine the dimensionality of each feature.
SELECT geotype, sde.st_coorddim (g1) coordinate_dimension
 FROM COORDDIM_TEST;

GEOTYPE               coordinate_dimension

Point                           2
Point Z                         3
Point M                         3
Point ZM                        4

PostgreSQL

--Create test table.
CREATE TABLE coorddim_test (
 geotype varchar(20),
 g1 sde.st_geometry
);

--Insert values to the test table.
INSERT INTO coorddim_test VALUES (
 'Point',
 st_point ('point (60.567222 -140.404)', 4326)
);

INSERT INTO coorddim_test VALUES (
 'Point Z',
 st_point ('point z (60.567222 -140.404 5959)', 4326)
);

INSERT INTO coorddim_test VALUES (
 'Point M',
 st_point ('point m (60.567222 -140.404 5250)', 4326)
);

INSERT INTO coorddim_test VALUES (
 'Point ZM',
 st_point ('point zm (60.567222 -140.404 5959 5250)', 4326)
);

--Determine the dimensionality of each feature.
SELECT geotype, st_coorddim (g1) 
 AS coordinate_dimension
 FROM coorddim_test;

geotype              coordinate_dimension

Point                          2
Point Z                        3
Point M                        3
Point ZM                       4

SQLite

--Create test tables and add geometry columns.
CREATE TABLE coorddim_test (
 geotype varchar(20)
);

SELECT AddGeometryColumn(
 NULL,
 'coorddim_test',
 'g1',
 4326,
 'pointzm',
 'xyzm',
 'null'
);

CREATE TABLE coorddim_test2 (
 geotype varchar(20)
);

SELECT AddGeometryColumn(
 NULL,
 'coorddim_test2',
 'g1',
 4326,
 'pointz',
 'xyz',
 'null'
);

CREATE TABLE coorddim_test3 (
 geotype varchar(20)
);

SELECT AddGeometryColumn(
 NULL,
 'coorddim_test3',
 'g1',
 4326,
 'pointm',
 'xym',
 'null'
);

CREATE TABLE coorddim_test4 (
 geotype varchar(20)
);

SELECT AddGeometryColumn(
 NULL,
 'coorddim_test4',
 'g1',
 4326,
 'point',
 'xy',
 'null'
);

--Insert values to the test table.
INSERT INTO coorddim_test4 VALUES (
 'Point',
 st_point ('point (60.567222 -140.404)', 4326)
);

INSERT INTO coorddim_test2 VALUES (
 'Point Z',
 st_point ('point z (60.567222 -140.404 5959)', 4326)
);

INSERT INTO coorddim_test3 VALUES (
 'Point M',
 st_point ('point m (60.567222 -140.404 5250)', 4326)
);

INSERT INTO coorddim_test VALUES (
 'Point ZM',
 st_point ('point zm (60.567222 -140.404 5959 5250)', 4326)
);

--Determine the dimensionality of features in each table.
SELECT geotype, st_coorddim (g1) 
 AS coordinate_dimension
 FROM coorddim_test;

geotype              coordinate_dimension

Point ZM                       4


SELECT geotype, st_coorddim (g1) 
 AS coordinate_dimension
 FROM coorddim_test2;

geotype              coordinate_dimension

Point Z                        3


SELECT geotype, st_coorddim (g1) 
 AS coordinate_dimension
 FROM coorddim_test3;

geotype              coordinate_dimension

Point M                        3


SELECT geotype, st_coorddim (g1) 
 AS coordinate_dimension
 FROM coorddim_test4;

geotype              coordinate_dimension

Point                          2