[postgis-users] Postgresql, postgis and PHP

[Pierre Racine]

This tutorial will show you how to do exactly what you want with rasters:

http://trac.osgeo.org/postgis/wiki/WKTRasterTutorial01

Pierre

________________________________________
From: postgis-users-bounces at postgis.refractions.net [postgis-users-bounces at postgis.refractions.net] On Behalf Of Louwrens du Toit [louwrence_du at eva.mpg.de]
Sent: Wednesday, February 02, 2011 5:24 AM
To: postgis-users at postgis.refractions.net
Subject: [postgis-users] Postgresql, postgis and PHP

Dear Postgis-Users List,

I'm an experienced web developer (mainly PHP, Javascript, MySQL) and
have recently started a job where I need work with geographic
information, mainly in a Postgresql database. So, I'm quite new to all
this geographical data etc and have a few questions:

So, I have a database (Postgresql) with geographical data (mainly
polygons in format "geometry" - srid 4326). Now I can do some area
(ST_Area) and intersection (ST_Intersection) queries but would like to
know the following:

1. I have several tables with polygon data (layers) but need to do
queries across them (what I need to do in the end is to create charts -
bar,pie etc). I.e I would like to know for instance, what percentage
area of layer 1 falls within the area in layer 2? or
2. I have raster data (in geotiff format), and would like to know... per
polygon (in layer 1 above), what is the mean value of the raster data...

Can someone point me in a direction of where to information like this.
How should I go about this problem?

I hope this makes sense. As I said, I'm very new to all this geographic
stuff.

Thank you,
LJ du Toit

--

__________________________________________________
LJ du Toit

_______________________________________________
postgis-users mailing list
postgis-users at postgis.refractions.net
http://postgis.refractions.net/mailman/listinfo/postgis-users