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

Performance of Java-based SQL processing

If a function is not available natively in Oracle, then having it become available via a custom Java function is a reasonable compromise! Even so, to be really useful, such code must operate correctly and efficiently.

Much has been written on the performance of PL/SQL against native SQL functionality, with some also available for Java-based stored procedures. From such work you can discover a set of guidelines for creating fast executing functions.

While little can be done about the cost to call a Java Stored Procedure from SQL (c.f., context swapping), one does have control over the efficiency of the implemented algorithm. JTS is particularly known for this, such that its algorithms are well understood. In addition methods that operate on an array or collection of geometry objects (c.f., ST_PolygonBuilder's processing of x and y collections), will result in faster operation than the methods that process only one geometry at a time, out of many. While...