[lug] BLUG Poll

[Rob Nagler]

Bruce Raup writes:
> Perhaps I'm the only one with this interest, but I'd be interested in
> hearing about geospatial applications using PostGIS.  I've been using
> PostGIS for some time now, but it would be good to hear about others'
> experiences.

I wrote a small production PostGIS app.  What I learned was that
PostGIS is merely a wrapper for proj and geos.  The only benefit of
PostGIS is that you can include the query in your SQL, which means you
get sorting.  However, the index seems to be based on a bounded box,
which isn't all that efficient for most interesting polygons
(counties, states, etc.).  Perhaps it's better than nothing, and it is
all OSS.

I also found that I had to do everything in EWKT.  PostGIS didn't know
how to return the SRID from the column unless I did -- It's been a
while, but that's what I remember happening.

If you are doing complex manipulations of small data sets, I'd
recommend going with proj and geos directly. 

Rob