首页 > 数据库 > 国内数据库 > YashanDB ST_MULTI函数
ST_MULTI函数用于返回输入的Geometry对象所对应的Geometry Collection类型。若输入的Geometry已是集合类型,则返回输入的Geometry对象。
geometry
通用表达式,其值必须为有效的ST_GEOMETRY类型的数据。
输入Geometry类型与返回Geometry类型的对应关系见下表:
|
输入类型 |
输出类型 |
|---|---|
|
Point |
MultiPoint |
|
LineString |
MultiLineString |
|
Polygon |
MultiPolygon |
|
MultiPoint |
MultiPoint |
|
MultiLineString |
MultiLineString |
|
MultiPolygon |
MultiPolygon |
|
GeometryCollection |
GeometryCollection |
示例
SELECT st_astext(st_multi(st_geomfromText('point(0 0)', 4326)), 0) multi FROM dual;MULTI----------------------------------------------------------------MULTIPOINT (0 0)SELECT st_astext(st_multi(st_geomfromText('linestring(0 0, 1 1)', 4326)), 0) multi FROM dual;MULTI----------------------------------------------------------------MULTILINESTRING ((0 0, 1 1))SELECT st_astext(st_multi(st_geomfromText('polygon((0 0, 1 1, 2 0, 0 0))', 4326)), 0) multi FROM dual;MULTI----------------------------------------------------------------MULTIPOLYGON (((0 0, 1 1, 2 0, 0 0)))SELECT st_astext(st_multi(st_geomfromText('multipoint(0 0, 1 1)', 4326)), 0) multi FROM dual;MULTI----------------------------------------------------------------MULTIPOINT (0 0, 1 1)SELECT st_astext(st_multi(st_geomfromText('multilinestring((0 0, 1 1),(2 2, 4 4))', 4326)), 0) multi FROM dual;MULTI----------------------------------------------------------------MULTILINESTRING ((0 0, 1 1), (2 2, 4 4))SELECT st_astext(st_multi(st_geomfromText('multipolygon(((0 0, 1 1, 2 0, 0 0)), ((10 0, 11 1, 12 0, 10 0)))', 4326)), 0) multi FROM dual;MULTI----------------------------------------------------------------MULTIPOLYGON (((0 0, 1 1, 2 0, 0 0)), ((10 0, 11 1, 12 0, 10 0)))SELECT st_astext(st_multi(st_geomfromText('geometrycollection(point(0 0), point(1 1))', 4326)), 0) multi FROM dual;MULTI----------------------------------------------------------------GEOMETRYCOLLECTION (POINT (0 0), POINT (1 1))
来自 “ ITPUB博客 ” ,链接:https://blog.itpub.net/70028812/viewspace-3085980/ ,如需转载,请注明出处,否则将追究法律责任。