SDO_TOPO_MAP.CREATE_TOPO

Format

SDO_TOPO_MAP.CREATE_TOPO_MAP(     
  topology         IN VARCHAR2,      
  topo_map         IN VARCHAR2,      
  number_of_edges  IN NUMBER DEFAULT 100,      
  number_of_nodes  IN NUMBER DEFAULT 80,      
  number_of_faces  IN NUMBER DEFAULT 30);

Description

Creates a TopoMap object cache associated with an existing topology.

Parameters

topology: Name of the topology. Must not exceed 20 characters.
topo_map: Name of the TopoMap object. (TopoMap objects are explained in TopoMap Objects.)
number_of_edges: An estimate of the maximum number of edges that will be in the TopoMap object at any given time. If you do not specify this parameter, a default value of 100 is used.
number_of_nodes: An estimate of the maximum number of nodes that will be in the TopoMap object at any given time. If you do not specify this parameter, a default value of 80 is used.
number_of_faces: An estimate of the maximum number of faces that will be in the TopoMap object at any given time. If you do not specify this parameter, a default value of 30 is used.

Usage Notes

The number_of_edges, number_of_nodes, and number_of_faces parameters let you improve the performance and memory usage of the procedure when you have a good idea of the approximate number of edges, nodes, or faces (or any combination) that will be placed in the cache associated with the specified TopoMap object. Spatial initially allocates memory cache for the specified or default number of objects of each type, and incrementally increases the allocation later if more objects need to be accommodated.

You can create more than one TopoMap object in a user session; however, there can be no more than one updatable TopoMap object at any given time in a user session.

For information about using an in-memory cache to edit topological elements, see Approaches for Editing Topology Data.

Using this procedure is equivalent to calling the constructor of the TopoMap class of the client-side Java API (described in Topology Data Model Java Interface).

Examples

The following example creates a TopoMap object named CITY_DATA_TOPOMAP and its associated cache, and it associates the TopoMap object with the topology named CITY_DATA. (The example refers to definitions and data from Topology Built from Topology Data.)

CALL SDO_TOPO_MAP.CREATE_TOPO_MAP('CITY_DATA', 'CITY_DATA_TOPOMAP');