Sdo_relate command

Question

i have got two oracle spatial layers, from two different databases but of the same location (Roads). one with field name
"ufi and geom."
UFI
BB06104925
other with
"pfi ufi and geom"
PFI
6318226
select pfi, sdo_relate( b.geom, c.shape, 'MASK=INSIDE querytype=WINDOW')='TRUE') from
b_tr_roads2 b, b_geo_roads2 c where b.pfi=6318226 and c.ufi='BB06104925'
Output
PFI
6318226
6318226
logically it should return one record but it returns two records. Does anybody can catch my error.
thanks

Answer 1

The SDO_RELATE command should only be used in the context of the WHERE clause, never in the SELECT clause.
You should rewrite this query:
select /*+ ordered */ pfi
from b_geo_roads2 c, b_tr_roads2 b
where b.pfi=6318226 and c.ufi='BB06104925'
and sdo_relate( b.geom, c.shape, 'MASK=INSIDE querytype=WINDOW')='TRUE';
However, since you are only comparing two geometries, it would be better to do this without an operator, using a function instead (assuming tolerance in user_sdo_geom_metadata is 0.05):
select pfi
from b_geo_roads2 c, b_tr_roads2 b
where b.pfi=6318226 and c.ufi='BB06104925'
and sdo_geom.relate( b.geom, 'inside' c.shape, 0.05) ='INSIDE';
[Edited by: dabugov on Jul 11, 2005 8:21 AM]