PostGIS Cookbook - Second Edition

Conventions used

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "We will import the firenews.csv file that stores a series of web news collected from various RSS feeds."

A block of code is set as follows:

SELECT ROUND(SUM(chp02.proportional_sum(ST_Transform(a.geom,3734), b.geom, b.pop))) AS population   FROM nc_walkzone AS a, census_viewpolygon as b  WHERE ST_Intersects(ST_Transform(a.geom, 3734), b.geom)  GROUP BY a.id;

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

SELECT ...