Flattening an array

Question

I know how to flatten the sdo_ordinates array...
select *
from table (
select a.geo.sdo_ordinates
from states a
where a.state = 'California');
But we now have a need to be able to flatten the
sdo_ordinate array so that we can access the ordinates
in a more natural form as the X and Y elements of a 2D
geometry.
I know this is wrong but something like...
select X, Y
from table (
select a.geo.sdo_ordinates
from states a
where a.state = 'California');
The preferred method for doing this is via a view.
I am on 8.1.7.4 so any approach needs to keep this in mind.
Any suggestions?
S.

Answer 1

Dan,
8.1.7.4 was more picky and needed a CAST() to make it work.
The version I implemented (+ the view) is as follows:
==========================================
DEFINE defaultSchema = 'GIS'
CREATE OR REPLACE TYPE &defaultSchema..Coord2DType AS OBJECT (
x number,
y number );
show errors
grant execute on &defaultSchema..Coord2DType to public with grant option;
create or replace type Coord2DSetType
as table of &defaultSchema..Coord2DType
grant execute on &defaultSchema..Coord2DSetType to public with grant option;
drop function GetCoord2D;
create or replace function GetCoord2D (p_shape in mdsys.sdo_geometry)
return &defaultSchema..Coord2DSetType deterministic
is
v_shape mdsys.sdo_geometry := p_shape;
i number := 1;
coords &defaultSchema..Coord2DSetType := Coord2DSetType();
coordOffset number;
begin
while i < v_shape.sdo_ordinates.count
loop
coordOffset := (i+1)/2;
coords.extend;
coords(coordOffset) := &defaultSchema..Coord2DType(null,null);
coords(coordOffset).x := v_shape.sdo_ordinates(i);
coords(coordOffset).y := v_shape.sdo_ordinates(i+1);
i := i + 2;
end loop;
return coords;
end;
grant execute on &defaultSchema..GetCoord2D to public with grant option;
select shape from propright.pr_a where rownum = 1;
show errors
DECLARE
coords &defaultSchema..Coord2DSetType := Coord2DSetType();
v_shape mdsys.sdo_geometry;
BEGIN
select shape into v_shape from propright.pr_a where rownum = 1;
coords := GetCoord2D(v_shape);
END;
select rownum,coords.*
from propright.pr_a a, table(CAST(GetCoord2D(shape) AS Coord2DSetType)) coords
where a.pr_id = 14353;
The view is:
create or replace view pr_p
as
select property_right_id as pr_id, mdsys.sdo_geometry(2001,NULL,MDSYS.SDO_POINT_TYPE(coords.x,coords.y,NULL),NULL,NULL) as shape
from propright.property_right a, table(CAST(gis.GetCoord2D(a.shape) AS gis.Coord2DSetType)) coords;
==========================================
I now use the view to export data to a shapefile. So
now we can export the polygon as a polygon or as
a point shapefile! (Believe it or not this is a legal
requirement that we have to meet.)
Thanks mate,
S.