[OSM-dev] Deleting TIGER node tags
Frederik Ramm
frederik at remote.org
Tue Jul 21 15:38:33 BST 2009
Hi,
Andy Allan wrote:
> Tiger node tags make up 85.43% of all node tags and take up:
[...]
I just did a little test, prepared an .osc document that removed the
node tags from about 1000 nodes:
http://www.openstreetmap.org/browse/changeset/1894387
It came out at roughly 10 node changes per second. I count 177m nodes
with TIGER tags, which means that the whole process would take about 200
days on one API thread. It might be slightly faster if you upload larger
or smaller chunks - would have to do some experimenting to find the
sweet spot. Time could also be saved by running it one the LAN (on dev),
but again probably not a lot.
The quickest way would obviously be to make the change directly in the
database, however I do not want to be the one who has to write an SQL
procedure that does the whole versioning and inserting into history
table right.
I wonder if it might make more sense to go for the middle ground and
write a Ruby script that used the standard API Node model code to
iterate over all the nodes and does the modification directly. Still
something that would require TomH's blessing but probably less strain on
database and network than the wholly external method, and less potential
for ugly failure than a SQL poetry contest.
A big problem if one wants to "do this right" is probably the changeset
traffic...
Bye
Frederik
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