Yes, PostGIS LINESTRINGS, no not ST_AsEWKT(). By similar configuration I mean shape. So I can identify two lines if they have a similar shape. No not ST_Distance()....and don't call me Shirley.
I also neglected to include the query in my previous post.
SELECT
a.id,
b.id FROM subsumed_secondary a
INNER JOIN subsumed_secondary b ON a.geom && b.geom AND
a.id <>
b.id WHERE dev.line_descriptor_2(simplify(a.geom,1.5)) = dev.line_descriptor_2(simplify(b.geom,1.5))
On Fri, Apr 25, 2008 at 12:07 PM, Colin Wetherbee <
cww@denterprises.org> wrote:
Rhys Stewart wrote:
The example I provided earlier was a very simplified model of the table I'm working with after a self join. The table in question contains geographic data (linestrings)
PostGIS LINESTRINGs?
> and I have written a function to return a
textual representation
Like ST_AsEWKT()? > so that I can easily identify lines with similar
configuration. I want to now select lines that are in close proximity to each other and have the same configuration. So this requires a self join (afaik). So, short of a function like the one that was posited earlier, is there a method using just plain old sql to get the results I desire?
Surely, you don't mean ST_Distance()?
What do you mean by "similar configuration"?
Colin