[OSM-dev] Idea about ways / meta-ways

[Raphaël Jacquot]

matthew-osm at newtoncomputing.co.uk wrote:

>   way - ordered list of segments

this is incorrect though. there's nothing to say the segments are ordered
for the segments to be ordered we'd need an extra segment_index integer 
column that would contain the id of the segment in the way, and the 
primary key on the ways_segments table that would contain (way_id, 
segment_index)

> I like the this idea a lot from the map-side of things, but have some serious
> problems with getting to this state. There are some non-trivial issues with
> breaking up an existing way in the database (which could be a tree, or even
> contain cycles) into a set of new ways. To keep this mail short (a first for
> me), I'll skip this for now.

I said that before :D