[OSM-talk] Triplicate ovelayed streets

[lewispusey]

Thanks for the info. I'll take a look. Its best to write tools that don't 
allow duplicates or have some method maybe a SQL table that doesn't allow 
duplicate orders of segment node combinations but I guess that isn't the 
direction OSM is headed yet. There was the error checking tool that was 
recently mentioned. My internet connection has been problematic.
Lewis
----- Original Message ----- 
From: "Jochen Topf" <jochen at remote.org>
To: "lewispusey" <lewispusey at earthlink.net>
Cc: <talk at openstreetmap.org>
Sent: Saturday, January 20, 2007 4:24 PM
Subject: Re: [OSM-talk] Triplicate ovelayed streets


On Sat, Jan 20, 2007 at 02:05:59PM -0500, lewispusey wrote:
> Kind of disturbing, I spent a long time putting in part of an interstate 
> (I 91) in VT USA . When checking southern portion I find there is a triple 
> overlayed street that so perfectly mirrors the matching segments that the 
> only way I discovered it was when moving segments of way that  were 
> duplicated by segments  underneath, Further the ordering of relationship 
> between objects is so bizzare that sometimes the underlying segment vansih 
> depending on the moved node order. Seems something that might be impotant 
> to database corruption.  As I originally layed this in as a very long way 
> an the added nodes to way, so I'm not sure if that was the problem. Do I 
> now have to undo a lot of work? Please check the southern end of the 
> roadway if you are interested in the problem. I also tend to upload 
> changes to the database and download changes and then save what I am 
> currently working on to my disk in case of internet interruption-outages, 
> etc. No one else is working this area so that shouldn't introduce merging 
> conflicts. Perhaps the database will update to reflect a more optimal 
> state of my data.

I have seen similar problems, some of them might be because of interrupted
database uploads: Say you add a few nodes, segments and ways. When you
upload the data the upload is interrupted for some reason. You re-do the
upload. Unfortunately the editor does not know whether the first upload
did not work at all or whether the upload worked but the acknowledgement
didn't reach the editor. So it has to upload the data again. The result
is that you see several nodes and/or segments and/or ways on top of each
other.

You can find some of these problems with Maplint. Have a look at it.

Jochen
-- 
Jochen Topf  jochen at remote.org  http://www.remote.org/jochen/ 
+49-721-388298