[OSM-dev] Duplicate data from Tiger import
steve at asklater.com
Tue Nov 28 09:48:15 GMT 2006
* @ 28/11/06 01:21:03 AM jburgess at uklinux.net wrote:
> On Sun, 2006-11-26 at 22:24 +0000, Jon Burgess wrote:
> > I noticed that Mapnik was taking much longer than normal to process some
> > areas of the US and have found that there are instances where the same
> > data is duplicated over 100 times. For example see:
> > http://www.openstreetmap.org/api/0.3/map?bbox=-84.316874,39.16047,-84.315683,39.161368
> > If this is displayed in JOSM there are only 5 distinct nodes and yet the
> > raw XML shows that each of the nodes, segments and ways is duplicated
> > 102 times.
> > I don't know whether this is a problem with the original tiger data or
> > the import process, but it looks like something needs to be done to
> > remove the redundant data.
> > Jon
> Today I tried devising an enhanced osm2pgsql.c which would exclude
> duplicate ways while generating the SQL. I've got something which seems
> to work and indicates that around 60% of all nodes and ways in the
> planet-061112 are duplicates.
How do you define a dupe?
Where are these things, are they in the US (eg the TIGER import) or
SteveC steve at asklater.com http://www.asklater.com/steve/
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