SDO_GEOM.SDO

Format

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

or

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

Description

Returns the length or perimeter of a geometry object.

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).

tol

Tolerance value (see Tolerance).

unit

Unit of measurement: a quoted string with unit= and an SDO_UNIT value from the MDSYS.SDO_DIST_UNITS table (for example, 'unit=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 meters.

count_shared_edges

For three-dimensional geometries only: the number of times to count the length of shared parts of edges if the input geometry contains any edges that are fully or partially shared. If specified, must be 1 (count each once) or 2 (count each twice). The default is 1.

This parameter is ignored for two-dimensional input geometries.

Usage Notes

If the input polygon contains one or more holes, this function calculates the perimeters of the exterior boundary and all holes. It returns the sum of all perimeters.

Examples

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

-- Return the perimeters of all cola markets.
SELECT c.name, SDO_GEOM.SDO_LENGTH(c.shape, m.diminfo) 
  FROM cola_markets c, user_sdo_geom_metadata m 
  WHERE m.table_name = 'COLA_MARKETS' AND m.column_name = 'SHAPE';

NAME                             SDO_GEOM.SDO_LENGTH(C.SHAPE,M.DIMINFO)         
-------------------------------- --------------------------------------         
cola_a                                                               20         
cola_b                                                       17.1622777         
cola_c                                                       9.23606798         
cola_d                                                       12.5663706

-- Return the perimeter of just cola_a.
SELECT c.name, SDO_GEOM.SDO_LENGTH(c.shape, m.diminfo) 
  FROM cola_markets c, user_sdo_geom_metadata m 
  WHERE m.table_name = 'COLA_MARKETS' AND m.column_name = 'SHAPE' 
  AND c.name = 'cola_a';

NAME                             SDO_GEOM.SDO_LENGTH(C.SHAPE,M.DIMINFO)         
-------------------------------- --------------------------------------         
cola_a                                                               20