ST_IsEmpty function

The ST_IsEmpty function takes a geometry as an input parameter and returns 1 if the given geometry is empty. Otherwise 0 (zero) is returned.

If the given geometry is null, then null is returned.

This function can also be called as a method.

Syntax

Parameter

geometry: A value of type ST_Geometry or one of its subtypes that represents the geometry that is to be tested.

Return type

INTEGER

Example

The following code creates three geometries and then determines if they are empty.


SET CURRENT FUNCTION PATH = CURRENT FUNCTION PATH, db2gse
CREATE TABLE sample_geoms (id INTEGER, geometry ST_Geometry)

INSERT INTO sample_geoms VALUES
       (1, ST_Geometry('point EMPTY',0))

INSERT INTO sample_geoms VALUES
       (2, ST_Geometry('polygon((40 120, 90 120, 90 150, 40 150, 40 120))' ,0))

INSERT INTO sample_geoms VALUES
       (3, ST_Geometry('multipoint m (10 10 5, 50 10 6, 10 30 8)' ,0))

INSERT INTO sample_geoms VALUES
       (4, ST_Geometry('linestring z (10 10 166, 20 10 168)',0))

INSERT INTO sample_geoms VALUES
       (5, ST_Geometry('point zm (10 10 16 30)' ,0))


SELECT id, ST_IsEmpty(geometry)  Is_Empty
FROM sample_geoms

Results:


ID          IS_EMPTY
----------- -----------
          1           1
          2           0
          3           0
          4           0
          5           0