ST_IsEmpty
Name
ST_IsEmpty — Tests if a geometry is empty.
Synopsis
boolean
ST_IsEmpty
(
geometry
geomA
)
;
Description
Returns true if this Geometry is an empty geometry. If true, then this Geometry represents an empty geometry collection, polygon, point etc.
This method implements the
OpenGIS Simple Features
Implementation Specification for SQL 1.1.
s2.1.1.1
This method implements the SQL/MM specification. SQL-MM 3: 5.1.7
Examples
SELECT ST_IsEmpty(ST_GeomFromText('GEOMETRYCOLLECTION EMPTY')); st_isempty ------------ t (1 row) SELECT ST_IsEmpty(ST_GeomFromText('POLYGON EMPTY')); st_isempty ------------ t (1 row) SELECT ST_IsEmpty(ST_GeomFromText('POLYGON((1 2, 3 4, 5 6, 1 2))')); st_isempty ------------ f (1 row) SELECT ST_IsEmpty(ST_GeomFromText('POLYGON((1 2, 3 4, 5 6, 1 2))')) = false; ?column? ---------- t (1 row) SELECT ST_IsEmpty(ST_GeomFromText('CIRCULARSTRING EMPTY')); st_isempty ------------ t (1 row)