Combined flat (regular) and Spatial query

Question

DB: Oracle 8.1.7.2.1 (8i Release 3, patch 81721)
I performed a spatial query on the results of a regular query, in the form of:
Select count(*) from
(select * from myTable where key=...)
WHERE (MDSYS.SDO_RELATE("GEOLOC",
MDSYS.SDO_GEOMETRY(2003,NULL,null,
MDSYS.SDO_ELEM_INFO_ARRAY(1,1003,3),
MDSYS.SDO_ORDINATE_ARRAY(-118.83939716391866,
29.951783100000025, -100.20650379608135,
40.52319191999998)),
'mask=ANYINTERACT layer_gtype=POINT
querytype = WINDOW')='TRUE');
The first flat query results in a small number of records and takes minimum time if run separately.
Select count(*) from
(select * from myTable where key=...)
However, when appended the spatial join condition, it takes a long time, same as querying from the whole dataset without the first flat query. I tried to optimize the spatial index and it did not help much.
Why isn't the spatial query taking advantage of the flat query? Can I somehow force it to do so to improve the performance? (This is a dynamic query in an application.)
Thanks.

Answer 1

Hi
I have a similar problem and i'd like to know if anyone have got a solution.
We are developing a vehicle localization system.
The amount of data it's about 6 million positions per year.
The queries to the data could be the actual location of the vehicle (100 vehicles) or historical locations.
For historical location we have partitioned the table an index by date (each week), and for actual location we have created a bitmap index based on field L_ULTIMA.
Allwais the queries are filtered by alfanumeric conditions more restrictive then spatial (range of dates or last_location).
When runnin alfanumeric queries over a subset of une million rows, it takes only few seconds (even less) but when including spatial conditions (SDO_RELATE to a rectangle) it takes more than one minute.
We have tried different hints to force the use of bitmap index but in all cases the execution plan uses de spatial index.
It's there any way to combine spatial and flat indexes?
SELECT
COUNT(*)
FROM SLFP_LOCALIZACIONES A
WHERE sdo_relate(A.geom, mdsys.sdo_geometry(2003,NULL,NULL,
mdsys.sdo_elem_info_array(1,1003,3),
mdsys.sdo_ordinate_array(159657,3978069, 546051,4116358)),
'mask=anyinteract querytype=window') = 'TRUE';
COUNT(*)
899073
Transcurrido: 00:02:126.34
SELECT /*+ INDEX_COMBINE(A SLFP_LOCALI_ULTIMA_I) */
COUNT(*)
FROM SLFP_LOCALIZACIONES A
WHERE sdo_relate(A.geom, mdsys.sdo_geometry(2003,NULL,NULL,
mdsys.sdo_elem_info_array(1,1003,3),
mdsys.sdo_ordinate_array(159657,3978069, 546051,4116358)),
'mask=anyinteract querytype=window') = 'TRUE' AND
A.L_ULTIMA = 1;
COUNT(*)
102
Transcurrido: 00:02:121.00
SELECT COUNT(*) FROM SLFP_LOCALIZACIONES WHERE L_ULTIMA = 1
COUNT(*)
104
Transcurrido: 00:00:00.72
SQL> SELECT /*+ INDEX_COMBINE(A SLFP_LOCALI_ULTIMA_I) */
2 COUNT(*)
3 FROM SLFP_LOCALIZACIONES A
4 WHERE N_X >= 159657 AND
5 N_X <= 546051 AND
6 N_Y >= 3978069 AND
7 N_Y <= 4116358 AND
8 A.L_ULTIMA = 1;
COUNT(*)
102
Transcurrido: 00:00:00.59