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

Working with GPS data


In this recipe, you will work with GPS data. This kind of data is typically saved in a .gpx file. You will import a bunch of .gpx files to PostGIS from RunKeeper, a popular social network for runners.

If you have an account on RunKeeper, you can export your .gpx files and process them by following the instructions in this recipe. Otherwise, you can use the RunKeeper .gpx files included in the runkeeper-gpx.zip file located in the chp03 directory available in the code bundle for this book.

You will first create a bash script for importing the .gpx files to a PostGIS table, using ogr2ogr. After the import is completed, you will try to write a couple of SQL queries and test some very useful functions, such as ST_MakeLine to generate polylines from point geometries, ST_Length to compute distance, and ST_Intersects to perform a spatial join operation.

Getting ready

Extract the data/chp03/runkeeper-gpx.zip file to working/chp03/runkeeper_gpx. In case you haven't been through...