10.1 SDO_GEOMETRY Objects in User-Defined Type Definitions

The SDO_GEOMETRY type can be embedded in a user-defined data type definition.

The procedure is very similar to that for using the SDO_GEOMETRY type for a spatial data column:

1. Create the user-defined data type.

2. Create a table with a column based on that data type.

3. Insert data into the table.

4. Update the USER_SDO_GEOM_METADATA view.

5. Create the spatial index on the geometry attribute.

6. Perform queries on the data.

For example, assume that you want to follow the cola markets scenario in the simplified example in Simple Example: Inserting_ Indexing_ and Querying Spatial Data, but want to incorporate the market name attribute and the geometry attribute in a single type. First, create the user-defined data type, as in the following example that creates an object type named MARKET_TYPE:

CREATE OR REPLACE TYPE market_type AS OBJECT 
  (name VARCHAR2(32), shape SDO_GEOMETRY);
/

Create a table that includes a column based on the user-defined type. The following example creates a table named COLA_MARKETS_2 that will contain the same information as the COLA_MARKETS table used in the example in Simple Example: Inserting_ Indexing_ and Querying Spatial Data.

CREATE TABLE cola_markets_2 (
  mkt_id NUMBER PRIMARY KEY,
  market MARKET_TYPE);

Insert data into the table, using the object type name as a constructor. For example:

INSERT INTO cola_markets_2 VALUES(
  1,
  MARKET_TYPE('cola_a',
    SDO_GEOMETRY(
      SDO_POLYGON2D,  -- two-dimensional polygon
      NULL,
      NULL,
      SDO_ELEM_INFO_ARRAY(1,1003,3), -- one rectangle (1003 = exterior)
      SDO_ORDINATE_ARRAY(1,1, 5,7) -- only 2 points needed to
            -- define rectangle (lower left and upper right)
      )
  )
);

Update the USER_SDO_GEOM_METADATA view, using dot-notation to specify the column name and spatial attribute. The following example specifies MARKET.SHAPE as the COLUMN_NAME (explained in COLUMN_NAME) in the metadata view.

INSERT INTO user_sdo_geom_metadata
    (TABLE_NAME,
     COLUMN_NAME,
     DIMINFO,
     SRID)
  VALUES (
  'cola_markets_2',
  'market.shape',
  SDO_DIM_ARRAY(   -- 20X20 grid
    SDO_DIM_ELEMENT('X', 0, 20, 0.005),
    SDO_DIM_ELEMENT('Y', 0, 20, 0.005)
     ),
  NULL   -- SRID
);

Create the spatial index, specifying the column name and spatial attribute using dot-notation. For example.

CREATE INDEX cola_spatial_idx_2
ON cola_markets_2(market.shape)
INDEXTYPE IS MDSYS.SPATIAL_INDEX_V2;

Perform queries on the data, using dot-notation to refer to attributes of the user-defined type. The following simple query returns information associated with the cola market named cola_a.

SELECT c.mkt_id, c.market.name, c.market.shape 
  FROM cola_markets_2 c
  WHERE c.market.name = 'cola_a';

The following query returns information associated with all geometries that have any spatial interaction with a specified query window, namely, the rectangle with lower-left coordinates (4,6) and upper-right coordinates (8,8).

SELECT c.mkt_id, c.market.name, c.market.shape
  FROM cola_markets_2 c
  WHERE SDO_RELATE(c.market.shape,
            SDO_GEOMETRY(SDO_POLYGON2D, NULL, NULL,
              SDO_ELEM_INFO_ARRAY(1,1003,3),
              SDO_ORDINATE_ARRAY(4,6, 8,8)),
            'mask=anyinteract');