Определение
ST_AsText берет геометрию и возвращает ее стандартное текстовое представление.
Синтаксис
Oracle и PostgreSQL
sde.st_astext (geometry sde.st_geometry)
SQLite
st_astext (geometry geometryblob)
Тип возврата
Oracle
CLOB
PostgreSQL и SQLite
Текст
Пример:
Функция ST_AsText преобразует точку hazardous_sites в текстовое описание.
Oracle
CREATE TABLE hazardous_sites (
site_id integer not null,
name varchar(40),
loc sde.st_geometry);
INSERT INTO HAZARDOUS_SITES (site_id, name, loc) VALUES (
102,
'W. H. KleenareChemical Repository',
sde.st_geometry ('point (1020.12 324.02)', 4326)
);
SELECT site_id, name, sde.st_astext (loc) Location
FROM HAZARDOUS_SITES;
SITE_ID NAME Location
102 W. H. KleenareChemical Repository POINT (1020.12000000 324.02000000)
PostgreSQL
CREATE TABLE hazardous_sites (
site_id serial,
name varchar(40),
loc sde.st_geometry);
INSERT INTO hazardous_sites (name, loc) VALUES (
'W. H. KleenareChemical Repository',
sde.st_point ('point (1020.12 324.02)', 4326)
);
SELECT site_id, name, sde.st_astext (loc)
AS location
FROM hazardous_sites;
site_id name location
102 W. H. KleenareChemical Repository POINT (1020.12000001 324.01999999)
SQLite
CREATE TABLE hazardous_sites (
site_id integer primary key autoincrement not null,
name varchar(40)
);
SELECT AddGeometryColumn(
NULL,
'hazardous_sites',
'loc',
4326,
'point',
'xy',
'null'
);
INSERT INTO hazardous_sites (name, loc) VALUES (
'W. H. KleenareChemical Repository',
st_point ('point (1020.12 324.02)', 4326)
);
SELECT site_id, name, st_astext (loc)
FROM hazardous_sites;
1 W. H. KleenareChemical Repository POINT (1020.12000000 324.02000000)