Does sdo_relate function work for 3 dimension geometry?

Question

Hi,
I've read in Pro Oracle Spatial book that Oracle spatial operators work only for two-dimensional geometries, except SDO_FILTER (pg 257).
I always declare geometries data in 3 dimension, like that:
MDSYS.SDO_ELEM_INFO_ARRAY(1,3,1), MDSYS.SDO_ORDINATE_ARRAY(-42.4149263501948,-19.409108499099,0,-42.4142138531992,-19.4092962878525,0)
Sometimes SDO_RELATE works, specially if it is a small polygon or a perfect square.
I need to prove to my boss that we have to work with 2 dimension, but he is arguing that if sometimes it works is because I'm doing something wrong when SDO_RELATE doesn't work.
Thanks for any help.
Best regards,
Luiz Soares
Message was edited by:
Luiz Soares

Answer 1

Hi Luiz,
If your data is 2d you should only be declaring it as 2d.
In Oracle 10g and earlier, sdo_relate only works on 2d data.
If you create a 3d index by explicitly creating your index with sdo_indx_dims=3, then sdo_relate is disabled.
If you create a 3d index as above, sometimes sdo_filter can actually return the same results as sdo_anytinteract. For instance, if you are using non-geodetic data, there are some cases (rectangular polygons aligned along x,y, and z axis, points, some combinations) where this is currently true.