Line Intersection retuns point instead line segment

Hi all,
I want to intersect two lines with the function sdo_intersection (Oracle8i).
However, as result I get always a point instead of a line segment.
Any suggestions ??
Thanks Peter
Following the Script:
/* Table Theme2 */
CREATE TABLE THEME2(ID NUMBER, GEOM MDSYS.SDO_GEOMETRY);
/* Update Metadata */
INSERT INTO USER_SDO_GEOM_METADATA (TABLE_NAME, COLUMN_NAME, DIMINFO)
VALUES ('THEME2', 'GEOM', MDSYS.SDO_DIM_ARRAY
(MDSYS.SDO_DIM_ELEMENT('X', 2546727.982208079, 2629500.677188804, 0.000000050),
MDSYS.SDO_DIM_ELEMENT('Y', 5479508.594623252, 5585930.631027042, 0.000000050) ) );
COMMIT;
/* Insert 2 Lines */
insert into theme2 values (1,SDO_GEOMETRY(2002, 82015, NULL,
SDO_ELEM_INFO_ARRAY(1, 2, 1),SDO_ORDINATE_ARRAY(
2546727.98, 5570612.31, 2551027.86, 5558787.64, 2554252.77,
5549112.91, 2570914.81, 5536213.27, 2580589.54, 5532988.36,
2612569.9, 5524657.34, 2621438.4, 5512563.92, 2622782.11, 5491870.75, 2629500.68, 5479508.59))
insert into theme2 values (2,mdsys.SDO_GEOMETRY(2002, 82015, NULL,
mdsys.SDO_ELEM_INFO_ARRAY(1, 2, 1), mdsys.SDO_ORDINATE_ARRAY(
2619288.46, 5585930.63, 2613913.61, 5568731.11, 2608538.76, 5550456.62,
2599132.77, 5535675.78, 2597789.06, 5527344.76, 2577095.89, 5517938.77, 2556671.46,
5513638.89, 2547534.21, 5509339.01))
/* Intersect */
select sdo_geom.sdo_intersection(b.geom,a.geom,0.05)
from theme2 a, theme2 b
where a.id=1 and b.id=2;
/* result */
TEST(SDO_GTYPE, SDO_SRID, SDO_POINT(X, Y, Z), SDO_ELEM_INFO, SDO_ORDINATES)
SDO_GEOMETRY(2001, NULL, NULL, SDO_ELEM_INFO_ARRAY(1, 1, 1), SDO_ORDINATE_ARRAY(2597969.08, 5528460.91))

The two lines you've provided intersect at a single point, which is by definition not a line.
If you want to return a line, then the intersection has to happen along some length of the line.
Also, whenever I look at geometries posted I always run sdo_geom.validate_geometry on the
data.
Your user_sdo_geom_metadata should include the srid value stored in the geometries.
The bounds of your user_sdo_geom_metadata should be a bit larger to encompass
both geometries.
Regards,
Dan

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