Thursday, June 7, 2007

Some ancient history - GIS database article from 1990!

In both my presentations at the last GITA conference, I included a few slides talking about my personal perspective on the history of geospatial technology moving into the mainstream, and Geoff Zeiss was kind enough to comment on this and say that he found it interesting. One of the main points I made was what a long time it has taken, and how we have been talking about moving to the mainstream for 20 years or so.

This prompted me to think that it might be interesting to elaborate on a few of these historical themes, in addition to looking at new developments. I managed to dig out of the (paper) archives (that makes me feel old!) the first significant article which I had published, "Exploiting Relational Database Technology in GIS", which first appeared in Mapping Awareness magazine in the UK in 1990, and a couple of slightly edited versions came out elsewhere over the next year or so. This reflected the work we were doing at IBM with our GFIS product at that time, using IBM's SQL/DS and DB2, and at the same time the Canadian company GeoVision was taking a similar approach using Oracle. Doug Seaborn of GeoVision presented a paper with some of the same themes at the 1992 AM/FM (now GITA) conference with the bold title "1995: the year that GIS disappeared" (note: when making visionary predictions, be wary about attaching dates to them :) !!). He had the right idea, saying that GIS would become absorbed into mainstream IT, he was just a decade or so ahead in terms of timing. As I remarked at GITA, we techies always tend to think that change will happen faster than it actually does. (As an aside, Doug has been out of the geospatial industry for a long time, but I got an email from him the other day saying that he was now back, and working for ESRI).

Anyway, back in those days these were fairly radical ideas - at the time, most systems used file-based (and tiled) systems for (primarily vector) graphics, and a separate database for alphanumeric data. It's interesting how things often go in cycles with many aspects of technology - we spent lots of effort getting to continuous databases and eliminating tiling, which has big advantages for editing linear and areal data, and now the big emphasis is on file-based tiled systems again for easy, fast and scalable distribution of data (but still with continuous database-oriented systems in the background to create and maintain the data).

I think that while this mainstream database approach was a good philosophy, Smallworld came out with its proprietary database in 1991, which had huge advantages over anything else available at the time - you could dynamically pan and zoom around very large continuous databases without having to extract data into small working datasets first, while more or less all the other approaches at that time (certainly those using the type of database approach described in my article) required you to do data extracts which typically took minutes rather than seconds. This delayed the uptake of the standard relational approach, since it just couldn't match the performance you could get with other approaches. Now 15+ years later, we have gone through 10 iterations of Moore's Law (performance doubling every 18 months), so computers are 1000 times faster and that goes a long way to overcoming those issues!

Quite by accident, I happened to be at the GIS 95 conference in Vancouver, when Oracle announced its new "Multidimension" product, which would later become Oracle Spatial. I met Edric Keighan there (now with CubeWerx), who led that development, and he told me that the development team had a copy of my article posted on their noticeboard as it articulated well what they were trying to achieve.

So anyway, after that rather meadering introduction, here is the article.

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