H2GIS

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ST_IsEmpty

Signature

BOOLEAN ST_IsEmpty(GEOMETRY geom);

Description

Returns true if geom is empty.

Implements the OpenGIS Simple Features Implementation Specification for SQL version 1.2.1.

Examples

SELECT ST_IsEmpty('MULTIPOINT((4 4), (1 1), (1 0), (0 3)))');
-- Answer: FALSE

SELECT ST_IsEmpty('GEOMETRYCOLLECTION(
                     MULTIPOINT((4 4), (1 1), (1 0), (0 3)),
                     LINESTRING(2 6, 6 2),
                     POLYGON((1 2, 4 2, 4 6, 1 6, 1 2)))');
-- Answer: FALSE

SELECT ST_IsEmpty('POLYGON EMPTY');
-- Answer: TRUE
See also