Book Image

Mastering Geoserver

By : Colin Henderson
Book Image

Mastering Geoserver

By: Colin Henderson

Overview of this book

Table of Contents (19 chapters)
Mastering GeoServer
About the Author
About the Reviewers

Creating SQL View layers

So far in this chapter, we have looked at publishing layers based on traditional database tables; so now, we will look at GeoServer's ability to create SQL View layers. A SQL View layer is a kind of dynamic layer within GeoServer that allows for a custom SQL script to be executed on each request for data. A SQL View layer can be used to perform complex database queries to derive content for a layer, for example, selecting all the points of a certain type within a polygon and adding a count value to that polygon. The generated polygon layer can then be rendered with a color ramp to show the range of values.

GeoServer SQL Views versus database views

You might be looking at this and thinking to yourself, "Why will I use a GeoServer SQL View over a database view?" There are a couple of reasons why GeoServer SQL Views might be preferable to database views:

  • You do not require access to the underlying database to create SQL View. However, you will require SQL-level access...