Extracting start/end vertex... no spatial index problem - please help!

Question

Hi All,
I've got a table of lines and i'm trying to create a view of the start and end points of each line. I've managed to do this but i want to display it as a layer in my wms and i keep getting the no spatial index error.
I've tried a couple of ways of doing this...
1) using getvertices and extracting the start and end, then reconstructing an sdo_geometry in the view - can quite understand the no spatial index error here.
2) using SDO_LRS.GEOM_SEGMENT_END_PT and SDO_LRS.GEOM_SEGMENT_START_PT - would of thought this would use the index on the base table?
Any other methods or help would be most appreciated..
Thanks

Answer 1

You might be able to do this using a function-based index (with no view). Here is a quick example (using a table I have):
DELETE FROM USER_SDO_GEOM_METADATA
WHERE TABLE_NAME = 'NTC_MAP_ROAD_HIGHWAY_AGGR'
AND COLUMN_NAME = 'MDSYS.SDO_LRS.GEOM_SEGMENT_START_PT(GEOMETRY)';
INSERT INTO USER_SDO_GEOM_METADATA (TABLE_NAME, COLUMN_NAME, DIMINFO, SRID)
VALUES ('NTC_MAP_ROAD_HIGHWAY_AGGR', 'MDSYS.SDO_LRS.GEOM_SEGMENT_START_PT(GEOMETRY)',
SDO_DIM_ARRAY
(SDO_DIM_ELEMENT('LONG', -180.0, 180.0, 0.5),
SDO_DIM_ELEMENT('LAT', -90.0, 90.0, 0.5)
8307);
COMMIT;
drop index NTC_MAP_ROAD_HWY_AGGR_FBSIDX;
create index NTC_MAP_ROAD_HWY_AGGR_FBSIDX
on NTC_MAP_ROAD_HIGHWAY_AGGR(MDSYS.SDO_LRS.GEOM_SEGMENT_START_PT(GEOMETRY))
indextype is mdsys.spatial_index;
select link_id, MDSYS.SDO_LRS.GEOM_SEGMENT_START_PT(GEOMETRY)
from NTC_MAP_ROAD_HIGHWAY_AGGR
where sdo_filter(MDSYS.SDO_LRS.GEOM_SEGMENT_START_PT(GEOMETRY),
sdo_geometry(2003,8307,null,sdo_elem_info_array(1,1003,3),
sdo_ordinate_array(-122.5,37.5,-122.3,37.7)))='TRUE';