Book Image

PostGIS Cookbook - Second Edition

By : Pedro Wightman, Bborie Park, Stephen Vincent Mather, Thomas Kraft, Mayra Zurbarán
Book Image

PostGIS Cookbook - Second Edition

By: Pedro Wightman, Bborie Park, Stephen Vincent Mather, Thomas Kraft, Mayra Zurbarán

Overview of this book

PostGIS is a spatial database that integrates the advanced storage and analysis of vector and raster data, and is remarkably flexible and powerful. PostGIS provides support for geographic objects to the PostgreSQL object-relational database and is currently the most popular open source spatial databases. If you want to explore the complete range of PostGIS techniques and expose related extensions, then this book is for you. This book is a comprehensive guide to PostGIS tools and concepts which are required to manage, manipulate, and analyze spatial data in PostGIS. It covers key spatial data manipulation tasks, explaining not only how each task is performed, but also why. It provides practical guidance allowing you to safely take advantage of the advanced technology in PostGIS in order to simplify your spatial database administration tasks. Furthermore, you will learn to take advantage of basic and advanced vector, raster, and routing approaches along with the concepts of data maintenance, optimization, and performance, and will help you to integrate these into a large ecosystem of desktop and web tools. By the end, you will be armed with all the tools and instructions you need to both manage the spatial database system and make better decisions as your project's requirements evolve.
Table of Contents (18 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Loading data from OpenStreetMap and finding the shortest path using A*


Test data is great for understanding how algorithms work, but the real data is often more interesting. A good source for real data worldwide is OpenStreetMap (OSM), a worldwide, accessible, wiki-style, geospatial dataset. What is wonderful about using OSM in conjunction with pgRouting is that it is inherently a topological model, meaning that it follows the same kinds of rules in its construction as we do in graph traversal within pgRouting. Because of the way editing and community participation works in OSM, it is often an equally good or better data source than commercial ones and is, of course, quite compatible with our open source model.

Another great feature is that there is free and open source software to ingest OSM data and import it into a routing database—osm2pgrouting.

Getting ready

It is recommended that you get the downloadable files from the example dataset that we have provided, available at http://www.packtpub...