ST_PERIMETER()

All functions > GEOSPATIAL > ST_PERIMETER()

Returns the perimeter of an areal geometry or geography.

Signatures

Perimeter

Returns: Perimeter of the input

ST_PERIMETER(geo: T) → DOUBLE

With:

• T : Custom types: GEOM_POINT | GEOM_LINESTRING | GEOM_POLYGON | GEOM_MULTIPOINT | GEOM_MULTILINESTRING | GEOM_MULTIPOLYGON | GEOM_MULTIANY | GEOG_POINT | GEOG_LINESTRING | GEOG_POLYGON | GEOG_MULTIPOINT | GEOG_MULTILINESTRING | GEOG_MULTIPOLYGON | GEOG_MULTIANY

Signature notes:

• On GEOMETRY: returns planar perimeter in SRID coordinate units
• On GEOGRAPHY: returns geodesic perimeter in meters
• Returns 0.0 for non areal sub kinds (Point, LineString)
• Not supported on Trino
• Returns NULL if the input is NULL

Examples

SELECT
    f1 := ST_PERIMETER(ST_GEOMFROMTEXT('POLYGON ((0 0, 10 0, 10 10, 0 10, 0 0))')) -- Perimeter of a 10x10 square
;