SDO_GEOM.SDO_SELF

Format

SDO_GEOM.SDO_SELF_UNION(     
  geom1  IN SDO_GEOMETRY,      
  dim1   IN SDO_DIM_ARRAY,      
) RETURN SDO_GEOMETRY;

or

SDO_GEOM.SDO_SELF_UNION(     
  geom1  IN SDO_GEOMETRY,      
  tol    IN NUMBER       
) RETURN SDO_GEOMETRY;

Description

Returns a valid geometry object that is the topological self union of one geometry object, which can be invalid.

Parameters

geom1: Geometry object.
dim1: Dimensional information array corresponding to geom1, usually selected from one of the xxx_SDO_GEOM_METADATA views (described in Geometry Metadata Views).
tol: Tolerance value (see Tolerance).

Usage Notes

This function can be used to fix the following problems that can make a geometry invalid:

Polygon boundary intersecting itself
Incorrect orientation of exterior or interior rings (or both) of a polygon

Examples

The following example returns a valid geometry object that is the topological self union of an invalid polygon.

-- Return the topological self union of an invalid geometry.
SELECT SDO_GEOM.SDO_SELF_UNION(
  SDO_GEOMETRY(2003, NULL, NULL, SDO_ELEM_INFO_ARRAY(1, 1003, 1), 
    SDO_ORDINATE_ARRAY(1, 1, 1, 4, 4, 4, 4, 1, 1, 1)), 
  0.00005) 
FROM dual;
 
SDO_GEOM.SDO_SELF_UNION(SDO_GEOMETRY(2003,NULL,NULL,SDO_ELEM_INFO_ARRAY(1,1003,1
--------------------------------------------------------------------------------
SDO_GEOMETRY(2003, NULL, NULL, SDO_ELEM_INFO_ARRAY(1, 1003, 1), SDO_ORDINATE_ARRAY(1, 4, 1, 1, 4, 1, 4, 4, 1, 4))