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
About the Authors
About the Reviewers
Table Comparing Simple Feature Access/SQL and SQL/MM–Spatial

Flashback queries

When applications are updating the database tables, some inadvertent action may cause data loss. Some bug in the application logic may cause the deletion of some data that is not supposed to be deleted. Oracle database provides very robust data recovery and backup features, but these are mostly used in case of media or hardware failures. The data loss caused by application or normal user actions often does not need the traditional data recovery mechanism provided by the database. the flashback feature of Oracle provides an easier to manage mechanism for recovering the data loss at the row-level or at the table-level. The main features of the flashback query are as follows:

  • Flashback Database: This restores the entire database to a specific point-in-time using Oracle-optimized flashback logs, rather than via backups and forward recovery.

  • Flashback Transaction: This undoes the effects of a single transaction, and optionally, all of its dependent transactions via a single...