Book Image

Applying and Extending Oracle Spatial

Book Image

Applying and Extending Oracle Spatial

Overview of this book

Spatial applications should be developed in the same way that users develop other database applications: by starting with an integrated data model in which the SDO_GEOMETRY objects are just another attribute describing entities and by using as many of the database features as possible for managing the data. If a task can be done using a database feature like replication, then it should be done using the standard replication technology instead of inventing a new procedure for replicating spatial data. Sometimes solving a business problem using a PL/SQL function can be more powerful, accessible, and easier to use than trying to use external software. Because Oracle Spatial's offerings are standards compliant, this book shows you how Oracle Spatial technology can be used to build cross-vendor database solutions. Applying and Extending Oracle Spatial shows you the clever things that can be done not just with Oracle Spatial on its own, but in combination with other database technologies. This is a great resource book that will convince you to purchase other Oracle technology books on non-spatial specialist technologies because you will finally see that "spatial is not special: it is a small, fun, and clever part of a much larger whole".
Table of Contents (20 chapters)
Applying and Extending Oracle Spatial
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Table Comparing Simple Feature Access/SQL and SQL/MM–Spatial
Index

Background to programming SDO_GEOMETRY


A spatial data type such as SDO_GEOMETRY defines a storage structure and processing functionality that is exposed through standardized SQL functionality.

If the type's storage structure is not accessible outside of the functions provided with the product, the ability to extend the core functionality of the type becomes dependent on the richness of the supplied functions. If that functionality is limited, nothing can be done because insufficient knowledge exists for accessing the underlying data, unless the vendor provides additional tools for accessing the data through low-level languages, such as C.

In Oracle's case, the SDO_GEOMETRY storage structure uses a SQL object type system that is composed of records/types, numbers, and arrays. This, coupled with powerful spatial and non-spatial functionality (for example, SQL99 analytics and pipelining), which is supplied with the database, creates a rich extensibility platform that allows for new functions...