Mapserver/PostGIS general questions about how best to do things

[Gerry Creager N5JXS]

Hmmm.  I thought I saw a discussion of doing #1 *on* the PostGIS list.
I seem to recall a general sentiment that the up-front work sould be
tedious but the overall result would be faster queries/maps.

Regards #2, I think you're treading on unploughed (plowed? it's still
early) ground for Mapserver.  I run into the same sort of thing with the
myriad of weather data I've got.  I've decided that, for my page, I'm
simply making a decision on what the users can get at.

HOWEVER, I believe a php-based page could render a new mapfile on the
fly while allowing column selections, and you could then work it by
calling that new mapfile.

I've not tried that.  Just a thought.

gerry

Stephen Woodbridge wrote:
> Hi all,
>
> I posted the bulk of this on the PostGIS list, but got not comments
> back. Since this is also mapserver oriented and the questions are
> general in nature, I'm hoping I might get some suggestions here.
>
> First, I have to say getting PostGIS up and running on freeBSD was very
> easy so Kudos to the port maintainer and freeBSD. Also get data loaded
> and get mapserver running with PostGIS was not nearly as hard as I had
> thought it might be and I'm really liking what I see, even if I'm not
> sure what to do with it all yet. Also getting mapserver running was just
> as easy.
>
> What I have done (and I will try to get you a link soon to see it) is
> load up the Census zipcode polygons and some of the Census summary File
> 1 and 3 data and I can generate some thematic maps.
>
> Questions:
>
> 1) What are your thoughts on loading all Tiger into PostGIS versus
> keeping most of it in shapefiles and only using some of the data out of
> PostGIS? Performance? Are there other benefits to put it all in PostGIS?
> If I had it all in PostGIS, are there other cool features that I could
> have that I don't now with shapefiles?
>
> 2) What is the best way to scale or other map an attribute column into a
> known range for use with mapserver CLASS EXPRESSIONS. The Census data
> has literally thousands of columns any of which you might want to select
> as the basis for a thematic map, or even some expression of multiple
> columns. Conversely, a mapfile would have some fixed number of classes
> that would say render you polygons as say shades of color based on the
> attributes.
>
> Has anyone done this? anyone have any ideas or suggestions on how to do
> this? I realize that 2) is slightly off topic, but any help would be
> appreciated.
>
> Thanks,
>   -Steve

--
Gerry Creager -- gerry.creager at tamu.edu
Texas Mesonet -- AATLT, Texas A&M University
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