ArcMap

ST_Area

Definition

ST_Area returns the area of a polygon or multipolygon.

Syntax

Oracle and PostgreSQL

sde.st_area (polygon sde.st_geometry)
sde.st_area (multipolygon sde.st_geometry)

SQLite

st_area (polygon st_geometry)
st_area (polygon st_geometry, unit_name)

Return type

Double precision

Example

The city engineer needs a list of building areas. To create the list, a GIS technician selects the building ID and area of each building's footprint.

The building footprints are stored in the bfp table.

To satisfy the city engineer's request, the technician selects the unique key, the building_id, and the area of each building footprint from the bfp table.

Oracle

--Create and populate table.
CREATE TABLE bfp (
 building_id integer not null,
 footprint sde.st_geometry);

INSERT INTO BFP (building_id, footprint) VALUES (
 1, 
 sde.st_polygon ('polygon ((0 0, 0 10, 10 10, 10 0, 0 0))', 4326)
);

INSERT INTO BFP (building_id, footprint) VALUES (
 2, 
 sde.st_polygon ('polygon ((20 0, 30 20, 40 0, 20 0))', 4326)
);

INSERT INTO BFP (building_id, footprint) VALUES (
 3,
 sde.st_polygon ('polygon ((20 30, 25 35, 30 30, 20 30))', 4326)
);

--Get area of geometries.
SELECT building_id, sde.st_area (footprint) Area
 FROM BFP;

BUILDING_ID       Area

          1        100
          2        200
          3         25

PostgreSQL

--Create and populate table.
CREATE TABLE bfp (
 building_id serial,
 footprint sde.st_geometry);

INSERT INTO bfp (footprint) VALUES (
 sde.st_polygon ('polygon ((0 0, 0 10, 10 10, 10 0, 0 0))', 4326)
);

INSERT INTO bfp (footprint) VALUES (
 sde.st_polygon ('polygon ((20 0, 30 20, 40 0, 20 0))', 4326)
);

INSERT INTO bfp (footprint) VALUES (
 sde.st_polygon ('polygon ((20 30, 25 35, 30 30, 20 30))', 4326)
);

--Get area of geometries.
SELECT building_id, sde.st_area (footprint) 
 AS Area
 FROM bfp;

building_id       area

          1        100
          2        200
          3         25

SQLite

--Create table, add geometry column to it, and populate the table.
CREATE TABLE bfp (
 building_id integer primary key autoincrement not null
);

SELECT AddGeometryColumn(
 NULL,
 'bfp',
 'footprint',
 4326,
 'polygon',
 'xy',
 'null'
);

INSERT INTO bfp (footprint) VALUES (
 st_polygon ('polygon ((0 0, 0 10, 10 10, 10 0, 0 0))', 4326)
);

INSERT INTO bfp (footprint) VALUES (
 st_polygon ('polygon ((20 0, 30 20, 40 0, 20 0))', 4326)
);

INSERT INTO bfp (footprint) VALUES (
 st_polygon ('polygon ((20 30, 25 35, 30 30, 20 30))', 4326)
);

--Get area of geometries.
SELECT building_id, st_area (footprint) 
 AS "area"
 FROM bfp;

building_id       area

          1        100.0
          2        200.0
          3         25.0

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