SDO_GEOM.SDO

Format

SDO_GEOM.SDO_AREA(     
  geom  IN SDO_GEOMETRY,      
  dim   IN SDO_DIM_ARRAY       
  [, unit  IN VARCHAR2]      
) RETURN NUMBER;

or

SDO_GEOM.SDO_AREA(     
  geom  IN SDO_GEOMETRY,      
  tol   IN NUMBER       
  [, unit  IN VARCHAR2]      
) RETURN NUMBER;

Description

Returns the area of a two-dimensional polygon.

Parameters

geom

Geometry object.

dim

Dimensional information array corresponding to geom, usually selected from one of the xxx_SDO_GEOM_METADATA views (described in Geometry Metadata Views).

unit

Unit of measurement: a quoted string with unit= and an SDO_UNIT value from the MDSYS.SDO_AREA_UNITS table (for example, 'unit=SQ_KM'). See Unit of Measurement Support for more information about unit of measurement specification.

If this parameter is not specified, the unit of measurement associated with the data is assumed. For geodetic data, the default unit of measurement is square meters.

tol

Tolerance value (see Tolerance).

Usage Notes

This function works with any polygon, including polygons with holes.

Lines that close to form a ring have no area.

Examples

The following example returns the areas of geometry objects stored in the COLA_MARKETS table. The first statement returns the areas of all objects; the second returns just the area of cola_a. (The example uses the definitions and data from Simple Example: Inserting_ Indexing_ and Querying Spatial Data.)

-- Return the areas of all cola markets.
SELECT name, SDO_GEOM.SDO_AREA(shape, 0.005) FROM cola_markets;

NAME                             SDO_GEOM.SDO_AREA(SHAPE,0.005)
-------------------------------- ------------------------------
cola_a                                                       24
cola_b                                                     16.5
cola_c                                                        5
cola_d                                               12.5663706

-- Return the area of just cola_a.
SELECT c.name, SDO_GEOM.SDO_AREA(c.shape, 0.005) FROM cola_markets c 
   WHERE c.name = 'cola_a';

NAME                             SDO_GEOM.SDO_AREA(C.SHAPE,0.005)
-------------------------------- --------------------------------
cola_a                                                         24