[Talk-GB] 'historic' county boundaries added to the database

Dave F davefoxfac63 at btinternet.com
Wed Aug 8 11:59:17 UTC 2018

On 08/08/2018 12:05, Lester Caine wrote:
> On 08/08/18 10:56, Dave F wrote:
>> On 08/08/2018 09:54, Lester Caine wrote:
>>> we are now in a situation where much accurately mapped material is 
>>> simply dumped when there is a change to the current situation.
>> 1. it's not dumped, it's still in the database as a historic version.
>> 2. Changes almost always increase the accuracy & detail of the database.
> Going back through the change logs is not the easiest process? 

Overpass API QL language offers means to do it using version() & a 
couple of other commands

> Isolating deletions that are due to historic changes rather than 
> simple factual corrections also muddies the water. But making the link 
> to OHM more organised would allow current valid data to be archived 
> properly?

It's possible to upload using JOSM, I believe (haven't used it), but I 
agree, a more open gateway for transferring would be useful.

>>> The 'delete' process should be handled in a manor more sensitive to 
>>> the hard work that has gone before!
>>> the vast majority of the material making up the historic data such 
>>> as boundaries IS the same as the current 'live' data.
>> I'm unsure that's true, but if it were, why duplicate?
> That was always my argument AGAINST OHM ... since much of the data 
> making up boundaries has not changed, having to duplicate that 
> information over to OHM, and then decide where material is current or 
> historic means that IDEALLY OHM is a complete copy of the OSM 
> database, but with the historic material easier to find than via 
> change sets ... why not just manage a single database? People who 
> don't want access to historic material simply ignore data which has 
> 'expired' via end_date.

How often do you believe people will actually want historic data? 
Organizations archive for a reason. Consider your house, how things you 
don't use will get shoved to the back of the cupboard/shed.
I live in a Roman city, the editors struggle to display current data. 
Imagine what it would be like if *everything* was shown back to the days 
of Emperor Nero.


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