What's New in the Topology and Network Data Models?

This section describes new and changed features of the Oracle Spatial topology and network data models for Oracle Database 11g Release 1 (11.1).

Load on Demand Analysis and Network Partitioning

To perform network analysis, you now have the option of partitioning the network and having needed partitions automatically loaded on demand during network analysis. This approach supplements the previous in-memory approach for network editing and analysis.

Note:

The in-memory approach will be deprecated in the next release of Spatial. Future development will enhance the load on demand approach, which you are encouraged use instead of the in-memory approach.

With the load on demand approach, you first partition the network into partitions of manageable size, and you use the load on demand Java API to perform analysis, which automatically loads and unloads needed partitions during analysis. This approach enables Spatial to perform network analysis on very large networks without memory limitation becoming a significant factor.

Load on demand analysis and network partitioning are described in Section 5.7.

Subpaths

A subpath is partial path along a path, created either as a result of a network analysis operation or explicitly by a user. The start and end points of a subpath are defined as link indexes and the percentage of the distance to the next node in the path. Subpaths are explained and illustrated in Section 5.3.

User Data Support

You can define your own data in the user data metadata view, and Spatial will manage the user data as well as the connectivity information. Each user data entry is stored as a column in node, link, path, and subpath tables. Spatial currently supports simple data types such as VARCHAR2, INTEGER, NUMBER, and SDO_GEOMETRY.

See the information about the include_user_data parameter for the SDO_NET.GENERATE_PARTITION_BLOB, SDO_NET.GENERATE_PARTITION_BLOBS, and SDO_NET.GET_PARTITION_SIZE subprograms.

XML API for Network Analysis

You can use the network data model XML API to perform network analysis. Web service requests are supported through Oracle Spatial Web services, which are described in Oracle Spatial Developer's Guide.

The XML schema of the network data model XML API is described in the following:

$ORACLE_HOME/md/doc/sdondmxml.zip