Fixed width data is probably the most annoying data to import because you need some mechanism to break the columns at the column boundaries. A lot of people bring this kind of data
into a tool such as OpenOffice, Excel or MS Access, massage it into a delimeted format and then pull it in with PostgreSQL copy command or some other means. There is another way and one that doesn't require
anything else aside from what gets packaged with PostgreSQL. We will demonstrate this way.
Its quite simple. Pull each record in as a single column and then spit it into the columns you want with plain old SQL. We'll demonstrate this by importing Census data places fixed width file.
Although this technique we have is focused on PostgreSQL, its pretty easy to do the same steps in any other relational database.
Both David Fetter and Dimitri Fontaine have demonstrated other approaches of doing this as well
so check theirs out.
We just finished the first draft of the last chapter of our book: First look at PostGIS WKT Raster. This completes our hard-core writing and now on to more drafting,
polishing all the chapters.
In Chapter 13 we demonstrate how to use PostGIS WKT Raster functions by example and cross breed with PostGIS geometry functionality. I was pleasantly surprised to see how nicely the raster and geometry functions play together.
We had intended this chapter to be short about 20 pages in length, because how much can one say about pixels and pictures. As it turns out, a lot.
Rasters are more versatile than their picture portrayal on a screen. Rasters are a class of structured storage suitable for representing any numeric,
cell based data where each cell has one or more numeric properties (the bands). This covers quite a bit of data you collect with remote sensing and other electronic instrumentation. We had to stretch to over 30 pages; even then we felt we were missing some critical examples.
There is a lot of useful functionality in PostGIS WKT Raster
already and should make a lot of people looking for raster support in PostgreSQL very happy. Although the chapter may portray some scenes of violence and torture inflicted on elephants, you can rest assured
that it is pure illusion and no real elephants or blue elephant dolls were harmed in the making of this chapter.
As a side note -- our book is now listed on Amazon PostGIS in Action.
It is not available in hard-copy yet,but you can pre-order and of course you can order from PostGIS in Action from Manning directly
to get the chapter drafts we have posted, updates as we polish them, and the final book when it comes out in hard print.
The Amazon listing would have been so much more exciting, had they not stripped me of my last name or had Leo married to himself. UPDATE: It appears I now have a last name again
In hind sight, I suppose OBE is more commonly seen as a title of honor rather than a last
name, so its only fitting that I should be stripped of mine and Tim Berners-Lee gets it tacked on at the end of his name.
To find out more about PostGIS WKT Raster, we encourage you to check out these links.
Today Microsoft unveiled their top secret project code named CatchMe.
This is their new flagship database for Linux and Unix based on predominantly the
PostgreSQL 9.0 code base, but with an emulation layer that makes it behave like SQL Server
2008 R2. Unlike the Windows SQL Server 2008 R2 product, this version is completely free and
open source under the Microsoft Public License (Ms-PL). Downloads for the RCs of these will be available soon. Please stay tuned.
Reporter Dat A. Base managed to get an exclusive interview with the head of the
project, Quasi Modo. The transcript follows: