SDO_NN doesn't work though tables are spatially indexed

Question

Hi,
As said Andrew Thomas, the Search function doesn't work today, so I don't know if the answer is already somewhere in the forum.
I' trying to perform a SDO_NN (nearest neighbor) search on a set of tables which are almost identical in structure. I first created a view in order to do 'ordinary' selects on the 'ordinary' columns.
Now I need to code request on spatial columns, with joins based on results from SDO_NN and values from ancillary function SDO_NN_DISTANCE.
As SDO_NN requires its first parameter to be a spatially indexed column and it is not possible to index a view, I create a temporary table on the fly, index it, insert a line into USER_SDO_INDEX_METADATA about this index and then launch my request.
I always get the following error:
ERROR at line 1 :
ORA-13249: SDO_NN cannot be evaluated without using index
ORA-06512: in "MDSYS.MD", ligne 1723
ORA-06512: in "MDSYS.MDERR", ligne 17
ORA-06512: in "MDSYS.PRVT_IDX", ligne 27
I've spent 3 days on it now, reading the manual for clues, adding optimizer hints, and so on.
Here comes the trace of my SQL script (with SET ECHO ON):
===================================================
SQL> @er_ens.sql
SQL>
SQL> DROP TABLE TEMPGEOMDATA ; -- Drop the temp table to be sure
DROP TABLE TEMPGEOMDATA
ERREUR � la ligne 1 :
ORA-00942: Table ou vue inexistante -- It didn't exist
SQL> DROP INDEX TEMPGEOMDATA_IDX ; -- Drop the temp index to be sure
DROP INDEX TEMPGEOMDATA_IDX
ERREUR � la ligne 1 :
ORA-01418: L'index indiqu� n'existe pas -- It didn't exist, either
SQL> DESCRIBE v$_er_ens; -- Display the view structure
Nom NULL ? Type
ADRESSE_NUMERO VARCHAR2(255)
ADRESSE_RUE VARCHAR2(255)
CLEF_DISTANCIER_GLOBAL VARCHAR2(255)
CODE_INSEE VARCHAR2(255)
DATE_CREATION DATE
DATE_MODIFICATION DATE
EFFECTIF_1997_1998 NUMBER
GEOMETRIE MDSYS.SDO_GEOMETRY
ID_FOURNISSEUR VARCHAR2(255)
INCLUS_DANS_LES_YVELINES VARCHAR2(255)
NOM VARCHAR2(255)
OBSERVATIONS_REMARQUES VARCHAR2(255)
RNE VARCHAR2(255)
SOURCE_DONNEES_GRAPHIQUES VARCHAR2(255)
STATUT VARCHAR2(255)
TYPE VARCHAR2(261)
SQL> SELECT Count(*) FROM v$_er_ens; -- Display the number of rows in the view
COUNT(*)
438
SQL> CREATE TABLE TEMPGEOMDATA AS SELECT * from v$_er_ens; -- Create temp table based on view
Table cr��e. -- Created
SQL>
SQL> DESCRIBE TEMPGEOMDATA; -- Display the temp table structure: all the same
Nom NULL ? Type
ADRESSE_NUMERO VARCHAR2(255)
ADRESSE_RUE VARCHAR2(255)
CLEF_DISTANCIER_GLOBAL VARCHAR2(255)
CODE_INSEE VARCHAR2(255)
DATE_CREATION DATE
DATE_MODIFICATION DATE
EFFECTIF_1997_1998 NUMBER
GEOMETRIE MDSYS.SDO_GEOMETRY
ID_FOURNISSEUR VARCHAR2(255)
INCLUS_DANS_LES_YVELINES VARCHAR2(255)
NOM VARCHAR2(255)
OBSERVATIONS_REMARQUES VARCHAR2(255)
RNE VARCHAR2(255)
SOURCE_DONNEES_GRAPHIQUES VARCHAR2(255)
STATUT VARCHAR2(255)
TYPE VARCHAR2(261)
SQL> SELECT Count(*) FROM TEMPGEOMDATA ; -- Display the number of rows in the temp table: the very same
COUNT(*)
438
SQL>
SQL> INSERT INTO -- Insert a new line in SDO_USER_INDEX_METADATA
2 USER_SDO_GEOM_METADATA
3 VALUES (
4 'TEMPGEOMDATA'
5 , 'GEOMETRIE'
6 , MDSYS.SDO_DIM_ARRAY(
7 MDSYS.SDO_DIM_ELEMENT('X', 56957200, 59045500, 0.005)
8 , MDSYS.SDO_DIM_ELEMENT('Y', 242450500, 244324700, 0.005)
9 )
10 , NULL
11 )
12 ;
1 ligne cr��e. -- Line inserted
SQL> SELECT * FROM USER_SDO_GEOM_METADATA WHERE TABLE_NAME LIKE 'TEMPGEOMDATA'; -- Check to be sure!
TABLE_NAME COLUMN_NAME DIMINFO SRID
TEMPGEOMDATA GEOMETRIE SDO_DIM_ARRAY(SDO_DIM_ELEMENT('X', 56957 NULL
200, 59045500, ,005), SDO_DIM_ELEMENT('Y
', 242450500, 244324700, ,005))
SQL> CREATE INDEX TEMPGEOMDATA_IDX -- Create the spatial index on temp table
2 ON "TEMPGEOMDATA" ("GEOMETRIE")
3 INDEXTYPE IS MDSYS.SPATIAL_INDEX
4 PARAMETERS (' SDO_INDX_DIMS=2 LAYER_GTYPE="COLLECTION"')
5 ;
Index cr��. -- Index created
SQL> show errors
Pas d'erreur. -- NO errors!
SQL> COMMIT;
Validation effectu�e. -- Commited to be sure!
SQL> SELECT -- Checking that every table involved has a spatial index
2 U.SDO_INDEX_NAME
3 --, A.OWNER
4 --, A.INDEX_TYPE
5 --, A.TABLE_OWNER
6 , A.TABLE_NAME
7 , A.STATUS
8 , A.PARAMETERS
9 --, A.JOIN_INDEX
10 FROM
11 USER_SDO_INDEX_METADATA U,
12 ALL_INDEXES A
13 WHERE
14 ( U.SDO_INDEX_NAME = A.INDEX_NAME )
15 AND (
16 ( A.TABLE_NAME LIKE '%TEMPGEOMDATA%' )
17 OR
18 ( A.TABLE_NAME LIKE '%BATSP_CIS%' )
19 OR
20 ( A.TABLE_NAME LIKE '%ENS%' )
21 )
22 ;
SDO_INDEX_NAME TABLE_NAME STATUS PARAMETERS
BATSP_CIS_SP_IDX BATSP_CIS VALID SDO_INDX_DIMS=2 LAYER_GTYPE="COLLECTION"
ENS_COLLEGE_SP_IDX ENS_COLLEGE VALID SDO_INDX_DIMS=2 LAYER_GTYPE="COLLECTION"
ENS_ECOLEPRIM_SP_IDX ENS_ECOLEPRIM VALID SDO_INDX_DIMS=2 LAYER_GTYPE="COLLECTION"
ENS_LYCEE_SP_IDX ENS_LYCEE VALID SDO_INDX_DIMS=2 LAYER_GTYPE="COLLECTION"
ENS_UIT_SP_IDX ENS_UIT VALID SDO_INDX_DIMS=2 LAYER_GTYPE="COLLECTION"
ENS_UNIV_SP_IDX ENS_UNIV VALID SDO_INDX_DIMS=2 LAYER_GTYPE="COLLECTION"
TEMPGEOMDATA_IDX TEMPGEOMDATA VALID SDO_INDX_DIMS=2 LAYER_GTYPE="COLLECTION"
7 ligne(s) s�lectionn�e(s). -- Yes, they all do (Join table, original tables for the view, temp table from the view)
SQL> SELECT /*+ INDEX(TEMPGEOMDATA TEMPGEOMDATA_IDX) INDEX(BATSP_CIS BATSP_CIS_SP_IDX INDEX LIMADM_COMMUNE LIMADM_COMMUNE_SP_IDX)*/
2 v.nom ENS_NOM
3 , v.adresse_numero -- Spatial request with
4 , v.adresse_rue -- optimizer hints to be sure indexes are used
5 , c.code_insee -- My understanding of manual is that only the
6 , c.nom COM_NOM -- 1st SDO_NN() parameter has to be spatially indexed
7 , b.code_centre -- i.e. alias 'b', table BATSP_CIS
8 , MDSYS.SDO_NN_DISTANCE(1) DIST -- which is the case!
9 FROM
10 --v$_er_ens v
11 TEMPGEOMDATA v
12 , limadm_commune c
13 , batsp_cis b
14 WHERE
15 ( v.code_insee = c.code_insee ) AND
16 ( SDO_NN(b.geometrie, v.geometrie, 'sdo_num_res=1', 1) = 'TRUE' )
17 ;
SELECT /*+ INDEX(TEMPGEOMDATA TEMPGEOMDATA_IDX) INDEX(BATSP_CIS BATSP_CIS_SP_IDX INDEX LIMADM_COMMUNE LIMADM_COMMUNE_SP_IDX)*/
ERREUR � la ligne 1 : -- An error occurs, though!
ORA-13249: SDO_NN cannot be evaluated without using index
ORA-06512: � "MDSYS.MD", ligne 1723
ORA-06512: � "MDSYS.MDERR", ligne 17
ORA-06512: � "MDSYS.PRVT_IDX", ligne 27
SQL> DELETE FROM
2 USER_SDO_GEOM_METADATA
3 WHERE
4 TABLE_NAME = 'TEMPGEOMDATA'
5 ;
1 ligne supprim�e. -- Deleted the line from USER_SDO_INDEX_METADATA, so it did exist!
SQL> DROP INDEX TEMPGEOMDATA_IDX ;
Index supprim�. -- Deleted the temp index, so it did exist!
SQL> DROP TABLE TEMPGEOMDATA ;
Table supprim�e. -- Deleted the temp table, so it did exist!
SQL>
SQL> SET ECHO OFF
SQL>
===================================================
Does anyone have a clue?

Answer 1

Hi,
As a general rule, whenever using an operator where the query window comes from a table rather than a constructor, try using the ordered hint and put the table that contains the query window (the second geometry in the operator) first in the from clause. You are right in that the table associated with the first geometry must be indexed. This query might be changed to:
SELECT /*+ ordered */
v.nom ENS_NOM, v.adresse_numero, v.adresse_rue,
c.code_insee , c.nom COM_NOM , b.code_centre,
MDSYS.SDO_NN_DISTANCE(1) DIST
FROM TEMPGEOMDATA v, limadm_commune c, batsp_cis b
WHERE v.code_insee = c.code_insee
AND SDO_NN(b.geometrie, v.geometrie, 'sdo_num_res=1', 1) = 'TRUE' ;
Hope this helps,
Dan