Understanding and using SDO_ORDINATES

When creating new spatial processing functions, sometimes only the SDO_GEOMETRY's array of ordinates (SDO_ORDINATES) need be processed. Two functions will be created that use two different methods for processing the ordinates. These functions are drawn from real-life situations that will be described.

Two things need to be understood about the SDO_ORDINATES attribute of the SDO_GEOMETRY object.

Firstly, the name of the SDO_GEOMETRY attribute that stores ordinate data is called SDO_ORDINATES, which is different from the underlying data type, which is called SDO_ORDINATE_ARRAY. This is the same as in a database table; an attribute may be called GID, but its data type Integer SDO_ORDINATE_ARRAY is defined as follows:

Create Or Replace  SDO_ORDINATE_ARRAY
    As VARRAY (1048576) Of Number;

Note

A VARRAY is a variable array.

The 1048576 ordinate limit can be removed at 11gR2 via execution of the sdoupggeom.sql script. See "A.3 Increasing the Size of Ordinate Arrays...