[postgis-users] Some general question about how best to do things

[Stephen Woodbridge]

Hi all,

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.

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 you thoughts on loading all Tiger into PostGIS versus 
keeping most of it in shapfiles 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