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

Physical and logical standby database


Oracle provides two features that support high availability of the database. In this context, availability is the extent to which a database is accessible on demand. The availability of a database is measured by the perception of an end user. A highly available system is accessible to the end users 24/7. A database might become unavailable due to hardware or software problems. The only way to build a highly available system in the face of hardware failure is to have a secondary or an alternate database running on a separate hardware system. A software failure or data corruption can also make the database unavailable. In such cases, a separate system can be used as a failover system such that all the users and applications can transparently use the second system while the primary system is being repaired. In high availability architecture, the main database is called the primary database and the secondary database is called the standby database. The standby...