Shady Project: Category GIS

Geographic Product Finder

Shady — Sun, 04 May 2008 22:30:00 -0700

So, another school project of mine ends up on the web: WorldBuy. It started life as my final project for CSE486 (Distributed Systems) but I liked it so much I decided to put it online.

Basically, you can click on a region and it will give you some general information about where you clicked. You can then search amazon for products related to that area. Products can be saved per region, and ranked so that a user can see what other people think are good products for a given place.

It's very, very, very beta at the moment. No user accounts, no per user places or products, and the search itself isn't particularly refined, but I think there is a lot of potential here.

It is also serving as a testbed for the new features I added to the geonames rubygem I wrote about in a previous blog post. The site makes use of both the paid account support, and the country info method. I made a custom rubygem with the new geonames features, and this site currently uses that.

I have a bunch of plans for features to add to this site, and I intend to keep working on this site. If you use it and like it, or don't like it, let me know!

Mapping Immigration and Language

Shady — Wed, 30 Apr 2008 16:39:00 -0700

For a final project in one of my classes, I made some maps of New York State language usage and foreign born population (the only measure of 'immigration' that the census bureau keeps track of).

The maps and a discussion about how they were made can be found here

Share and enjoy, if you have any comments leave them attached to this blog post.

In different area codes....

Shady — Wed, 19 Mar 2008 06:49:00 -0700

This is, without a doubt, the best map I have ever seen. I'm actually jealous that I didn't think of it first. You can find a larger version of it here.

RDMBS and Spatial Data on OS X

Shady — Tue, 23 Jan 2007 15:07:00 -0800

MySQL is nice enough for your average web application. Even larger applications can be run on it with the appropriate amount of tuning voodoo (see: wikipedia). There is even the MySQL MaxDB product (essentially SAPDB rebranded after its GPL release) available for Enterprise level MySQL, although this is not available for OS X.

Core data is also a nice solution for persistence inside a single application.

Oracle can also be run on OS X, provided you enjoy being turned upside down and shaken over a large funnel until all your money comes out. Not that this pertains specifically to Oracle on OS X, it's really more of an Oracle feature in general.

Each of these database server options are available for OS X. And they all have their various uses and proponents. So why am I here talking about Postgres? Well,

It's Free (speech, and beer).
It's enterprise ready (I seem to recall the .org primary name servers run on postgres)
PostGIS

For those who don't know, PostGIS is an addon for PostgreSQL that allows the use of geographic objects as native datatypes inside the SQL engine. This includes points, lines, polygons, as well as a variety of functions that can work with these data types to give us, say, area, intersection, and unions of the various objects. To use the industry parlance, PostGIS will "spatially enable" PostgreSQL which allows us to store a wide variety of geographic data. We can additionally point tools such as Quantum GIS, GRASS GIS, and even the various ARC tools at a PostgreSQL database for almost all of our spatial data storage needs. It is based on the Open Geospatial Consortium Simple Features Specification for SQL.

Storing spatial data in an RDMBS solves a wide variety of problems that happen when managing spatial data, especially with multiple users. We can manage concurrent access more easily, we have defined mechanisms for backing up the data, and we can even generate other file types (shapefiles, for example) from the data in the database. Any organiziation that has more then a few users working on large amounts of spatial data can benefit a lot through the use of a spatially enabled RDMBS

So why PostgreSQL then? Well, to my knowledge there is no equivalent library for MySQL (feel free to point my in the right direction if one does exist). Ditto for MaxDB. Oracle does have spatial extensions, but costs, to use a technical term, assloads of money. DB2 and MSSQL 2000 also have their own spatial extension, but fall into largley the same category as Oracle with regards to price. Although, there is a free spatial extension for MSSQL 2000 available, the price of the server itself is costly. Oh yeah, and neither one of those two run on OS X. PostgreSQL does.

Over the course of the week, I wil be writing more about setting up PostgreSQL on OS X (it's really not that hard), installing PostGIS, and getting everything working nice and happily. Time permitting, I will even experiment with the BaseTen framework. This library gives us all the ease of a CoreData-like API, with a PostegreSQL back end. Heck, with those two, we're halfway to a Cocoa Native GIS program. Wouldn't that be cool?

Stay tuned tomorrow, when I delve into the mysteries of PostgreSQL, OS X, and kern.sysv.shmmax.