Creating a view with existing GeoRaster columns and new SDO_GEOMETRY column

Question

Hi,
In a nutshell, I already have 1 real table, which has several attributes including types such as text, numbers etc. but also a GeoRaster column. This table works great, has its metadata stored properly and is spatially indexed; no worries.
I am then creating a view based on the above mentioned table, including the GeoRaster column. This worked, no problems. However now I want the same view to also have a SDO_GEOMETRY column which explicitly stores the spatial extent for each GeoRaster. Note the original table does not have this SDO_GEOMETRY column. So, I have created a revised SQL statement to create the view, but now it dynamically adds a new column and puts the GeoRaster.spatialextents into the SDO_GEOMETRY column.
This worked, the data made it into the view, but when we try to view the SDO_GEOMETRY in a viewer, we get errors. I added a system metadata entry for the view, but this did not help. Also, it is not possible to spatially index a view so I knew that was not the problem.
I think what has happened is the SDO_GEOMETRY column is in a sort of "limbo", where because it was not contained in the original table (and indexed there) and it is not able to be indexed in a view, it cannot be manipulated/viewed/used spatially.
Here is a snippet describing the original table:
"IMAGERY_ID" NUMBER NOT NULL ENABLE,
"CAM_ANGLE_X" NUMBER,
"CAM_ANGLE_Y" NUMBER,
"CAM_ANGLE_Z" NUMBER,
"SPEED" NUMBER,
"HEADING" NUMBER,
"IMAGE_GEOR" "SDO_GEORASTER",
"ACQUISITION_TIME" TIMESTAMP (6),
"SENSOR_ID" NUMBER,
"DOWNWARD_LOOKING" CHAR(1 BYTE),
"ORG_ID" NUMBER,
"POC_ID" NUMBER,
"FILE_NAME" VARCHAR2(100 BYTE),
"CORRELATION_ID" VARCHAR2(256 BYTE),
And here is the statement I used to create the new view:
CREATE VIEW level_0_img_view (imagery_id, cam_angle_x, cam_angle_y, cam_angle_z, speed, heading, image_geor, acquisition_time, sensor_id, downward_looking, org_id, poc_id, file_name, correlation_id, geor_extents)
AS
SELECT a.imagery_id, a.cam_angle_x, a.cam_angle_y, a.cam_angle_z, a.speed, a.heading, a.image_geor, a.acquisition_time, a.sensor_id, a.downward_looking, a.org_id, a.poc_id, a.file_name, a.correlation_id, a.image_geor.spatialextent
FROM imagery a
WHERE a.file_name LIKE '%.lev0';
Note in the above statement that the "geor_extents" column is the new column added dynamically (and not in the original table). Note the new column with the SDO_GEOMETRY data is flawless, I have looked at the records in SQL developer and all the data is there.
Any ideas?
In case you're wondering, I do have reasons for: (i) wanting an explicit column with the SDO_GEOMTRY (serving via WFS), and (ii) not wanting to alter the original table to include the equivalent SDO_GEOMETRY column.
Cheers,
M.

Answer 1

Hi,
if you are having problems to display your view spatial columns in MapBuilder/MapViewer, you may be missing to register the view information in the metadata (name and spatial columns).
For example, lets see the following table that simulates your case:
SQL> desc pci_image;
Name Null? Type
GEORID NOT NULL NUMBER
TYPE VARCHAR2(32)
GEORASTER MDSYS.SDO_GEORASTER
-- create a view
create view pci_img_view (georid,georaster,geor_extents)
as
select a.georid,a.georaster,a.georaster.spatialextent
from pci_image a;
-- register metadata for view spatial columns (GeoRaster and geometry column)
insert into user_sdo_geom_metadata
select 'PCI_IMG_VIEW','GEORASTER.SPATIALEXTENT', diminfo, srid
from user_sdo_geom_metadata where table_name = 'PCI_IMAGE'
insert into user_sdo_geom_metadata
select 'PCI_IMG_VIEW','GEOR_EXTENTS', diminfo, srid
from user_sdo_geom_metadata where table_name = 'PCI_IMAGE'
There is no need to index the spatial columns if they have been indexed before.
Now, if you go in MapBuilder you should see the the view name in the list of geometry tables, and be able to create a theme on column GEOR_EXTENTS (select it on the combo box) and to preview it.
For the GeoRaster column, currently the view name is not shown on the list of GeoRaster tables in MapBuilder.
For GeoRaster data, MapBuilder uses the contents of metadata view user_sdo_geor_sysdata, and then it would be needed to register the view contents there. We will talk with Jeffrey to check if there is any problem in registering
view contents in this metadata view. If the view name and georaster column is registered in user_sdo_geor_sysdata,
then it should show in MapBuilder. But you can still create a GeoRaster theme for this view using a SQL command, and should be able to preview it in MapBuilder.
-- create a GeoRaster theme based on view Georaster column.
insert into user_sdo_themes values (
'PCI_IMAGE_V_GEOR',
'View of georaster column',
'PCI_IMG_VIEW',
'GEORASTER',
'<?xml version="1.0" standalone="yes"?>
<styling_rules theme_type="georaster" raster_id="1" raster_table="RDT_PCI" raster_bands="0,1,2">
</styling_rules>');
-- commit changes
commit;
Joao