Oracle Spatial User's Guide and Reference - InfoLab

SDO_GEOMETRY Objects in Function-Based Indexes
create or replace function get_long_lat_pt(longitude in number,
latitude in number)
return SDO_GEOMETRY deterministic is
begin
return sdo_geometry(2001, 8307,
sdo_point_type(longitude, latitude, NULL),NULL, NULL);
end;
/
If the spatial data table does not already exist, create the table and add data to it, as
in the following example that creates a table named LONG_LAT_TABLE:
create table LONG_LAT_TABLE
(longitude number, latitude number, name varchar2(32));
insert into LONG_LAT_TABLE values (10,10, 'Place1');
insert into LONG_LAT_TABLE values (20,20, 'Place2');
insert into LONG_LAT_TABLE values (30,30, 'Place3');
Update the USER_SDO_GEOM_METADATA view, using dot-notation to specify
the schema name and function name. The following example specifies SCOTT.GET_
LONG_LAT_PT(LONGITUDE,LATITUDE) as the COLUMN_NAME (explained in
Section 2.4.2) in the metadata view.
-- Set up the metadata entry for this table.
-- The column name sets up the function on top
-- of the two columns used in this function,
-- along with the owner of the function.
insert into user_sdo_geom_metadata values('LONG_LAT_TABLE',
'scott.get_long_lat_pt(longitude,latitude)',
sdo_dim_array(
sdo_dim_element('Longitude', -180, 180, 0.005),
sdo_dim_element('Latitude', -90, 90, 0.005)), 8307);
Create the spatial index, specifying the function name with parameters. For
example:
create index LONG_LAT_TABLE_IDX on
LONG_LAT_TABLE(get_long_lat_pt(longitude,latitude))
indextype is mdsys.spatial_index;
Perform queries on the data. In the following example, the two queries accomplish
the same thing; however, the first query does not use a user-defined function
(instead using a constructor to specify the point), whereas the second query uses the
function to specify the point.
Extending Spatial Indexing Capabilities 9-5