Book Image

Applying and Extending Oracle Spatial

By : Siva Ravada, Simon Greener
Book Image

Applying and Extending Oracle Spatial

By: Siva Ravada, Simon Greener

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

Introducing different types of replication


An organization might want to serve users in different geographies from a central database. If the datacenter is located in the US, and some of the users are located in Asia, the network latency for the database queries generated in Asia might be longer than the expected response time for the application. In such cases, the organization might want to maintain another local database in a datacenter in Asia. Once a second database is added to the system, these two databases have to be maintained in sync with each other so that the users in Asia see the same results as the users in the US. Another example is the duplication of state level data sets in the local state plane projection at a state level database, while the national database has the same data in a geodetic system. One way to achieve this data duplication is to use a replication strategy to push the changes from one database to the other database. In this distributed system, there are different...