PostGIS中创建可以同时保存Polygon和MultiPolygon的字段

创建

CREATE table geometry_table(
  gid serial primary key,
  geom geometry(geometry,4326)
);

添加两个要素

INSERT INTO geometry_table(geom) VALUES ('SRID=4326;MultiPolygon EMPTY'),('SRID=4326;Polygon EMPTY');

查看刚刚添加的要素

SELECT st_asgeojson(geom) AS geom FROM geometry_table;

geom
{“type”:”MultiPolygon”,”coordinates”:[]}
{“type”:”Polygon”,”coordinates”:[]}