SDM
SDM White Paper (pdf, 194KB)
Technical Specification (pdf, 107KB)
- Spatial Data Managed in RDBMS
- Rapid Retrieval
- Enterprise Access
- Industry Standard RDBMS Compatibility
- Enhanced RDBMS Performance
- ODBC Compliant API
- Spatially Extended SQL
- Topological Data Types
- Version Management
- Circular Arcs
Storage and rapid retrieval of spatial data from your existing relational database is now a reality. The walls between corporate and spatial data have been removed allowing full access to GIS, MIS, AM/FM, geographic analysis and data "mining" applications.
SDM is SPATIALnet's RDBMS preprocessor which enables large volume storage of both spatial and aspatial corporate data in the one database environment. The key design feature of SDM is that it provides the capability for enterprise-wide access to all corporate data. This overcomes the principal limitation of the current generation of mainstream GIS products which use proprietary formats for spatial data storage.
Today's RDBMS technology is highly optimised for storage, retrieval and manipulation of large databases. The technology is mature, proven and improving constantly. By extending the RDBMS model, SDM in conjunction with SPATIALnet brings the power of RDBMS to spatial information. SDM enhances the power of the RDBMS without loss of functionality.
An extensive range of spatial data types and the ability to design logical views which are independent of the application software, make SDM and SPATIALnet an excellent tool for handling a broad range of spatial applications. Wide choice in spatial data types allows data to be modelled in the most appropriate way for intended applications. In addition the object based data model supports progressive implementation of large systems.
SDM supports an ODBC compliant API with spatial extensions. It also supports a spatially extended SQL scripting language for RAD and adhoc queries. Applications may be partitioned at link-time or run-time between 1-tier, 2-tier, and 3-tier architecture for enhanced scalability.
Since users retain access to the full set of relational database management system capabilities (such as forms data entry and query, report writers, security mechanisms, networking, transaction logging and end-user facilities), developing and deployment of the spatial application is considerably simplified.
Open Access:
SDM is committed to supporting open access to spatial data. Industry standard RDBMSs are the foundation for this openess. The SDM API complies with the level 1 ODBC standard. SDM supports SQL with spatial extensions as an interactive query language and as an ambedded language in user applications.
Platform Availability:
SDM client and server applications are only limited by the platforms supported by the RDBMS. This demonstrates SDM's openess. Full details of platforms are available in the current SDM Technical Specification.
Databases Supported:
Mainstream RDBMS's are supported including Oracle 7&8 and Microsoft SQL Server 7. Supported versions and configurations are available in the current SDM Technical Specification.
Performance:
Unique spatial indexing methods ensure high performance in the retrieval of data by spatial qualifier, for example "all poles within 1 kilometre of expressway".
Benefits:
Much of the power and flexibility of SDM stems from the extended relational data model. Unlike most spatial data processing systems, SDM allows considerable variation in schema for a SPATIALnet database, so that the database design can be moulded to the application. Specific benefits of SDM include:
- Fast retrieval from large spatial and aspatial databases. Database size has minimal effect on retrieval times.
- Storage and indexing of spatial and aspatial data, performed using the standard facilties of the host RDMBS.
- No loss of access to any of the facilities of the host RDBMS. This includes data security, data integrity, concurrency and locking, transaction recovery, journalling, backup and restoration.
- wide variety of data types based on the Spatial Data Transfer Standard (SDTS).
- Flexibility in the design of schemas for spatial databases through the use of direct and /or topological structures.
- Assurance of rigorous geometric and referential integrity for spatial data types.
|
