[OSM-talk] osm2pgsql & planet: frustrations, cutoffs, and idempotence

[Michal Migurski]

On Oct 27, 2008, at 12:59 AM, Martijn van Oosterhout wrote:

> On Mon, Oct 27, 2008 at 1:10 AM, Michal Migurski <mike at stamen.com>  
> wrote:
>> The final event in each weekly planet dump does not fall on an even
>> day boundary. In the case of the most recent Oct. 22nd planet.osm, it
>> was necessary to experiment with hourly diffs from that day to find
>> that the boundary was approx. 2:00pm. Hourlies up to and including
>> 2008102213-2008102214.osc.gz failed, hourlies after that succeeded. I
>> could go more granular here, checking the minute diffs as well for a
>> more precise breakpoint, but it seems odd that the planet dump does
>> not break cleanly on a midnight boundary so that it's possible to  
>> pick
>> up the differences moving forward.
>
> As I recall, osm2pgsql did support this kind of operation (or at least
> it did last time I tried, it was discussed on the list). All creates
> in diffs are treated as delete+insert. You don't actually say what the
> error was you ran into though so I can't be sure if you're talking
> about the same problem.
>
> Now that I think about it though, I think what I did was take one of
> the planet dumps from http://hypercube.telascience.org/planet/ (which
> *are* consistant snapshots), and run the dailies from there.

Is there any reason to not use those? They seem to be more frequent  
than the planet.openstreetmap.org ones - is there some disadvantage?  
How are they created?

-mike.

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michal migurski- mike at stamen.com
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