Hi Pierre, you should be asleep by now :) Hope the Snow is not too deep either :)
I did not know about that the HOT Private Store. Is that rendered on the OSm Layer or otherwise available? Would be interested in knowing a little bit more about that. Selecting objects in Sql is very dependent on the indexing. using + or <> with an index is very efficient. Using Like "haiyan%" can be reasonably fast if the data in the tag starts with the term you are searching for (eg: "haiyan") (case conversion will have an impact depending on the size of the string). If your search term is in the middle of the key data, eg; "damaged: haiyan: debris" it will be VERY slow as that will trigger a sequential scan I have my own planetosm database, if the crisis is not a seperate tag, ie, embedded within one tags data, I would set a trigger on the update that extracted the crisis name, eg: haiyan, and stored it in an indexable column. This is not particularly efficient, but I would have no choice as I think it is very important to be able to extract data specific to a Crisis. If you think about Overpass Queries, they would also not handle the data embedded in the tag particularly well, I am sure they could do it, but it would be subject to the same issue above. One possible solution would be to use the Postgres HStore, which is basically a text field. Postgres does have a unique ability to index data withing the hstore, but I would not use this method on my production database. Osm does have these tags already defined, I am sure you are aware - building:condition <http://wiki.openstreetmap.org/wiki/Key:building:condition>=* *for the condition of the building* - ruins <http://wiki.openstreetmap.org/wiki/Key:ruins>=* - *for ruins of buildings* - abandoned <http://wiki.openstreetmap.org/wiki/Key:abandoned>=* - *for a building * My thought would to NOT use these, as the fact that a building was tagged as abandoned is relevant in assessing if you want to assess it in a Humanitarian Crisis. Regards Mark Cupitt "If we change the world, let it bear the mark of our intelligence" See me on Open Street Map <https://www.openstreetmap.org/user/Mark_Cupitt> See me on LinkedIn <http://ph.linkedin.com/in/markcupitt> *See me on StackExchange <http://gis.stackexchange.com/users/17846/mark-c>* =============================================================================================== The contents of this email are intended only for the individual(s) to whom it is addressed and may contain confidential or privileged information. If you are not the intended recipient, you must not disclose, copy, distribute, or use the contents of this email. If you have received this email in error, please notify the sender immediately and delete the email and any attachments. =============================================================================================== On Fri, Jan 23, 2015 at 11:41 AM, Pierre Béland <[email protected]> wrote: > Mark > > About the prefix hot:, this is reserved for the HOT private store. Adding > this prefix to objects in JOSM, the objects are saved in the HOT private > store. > > Pierre > > ------------------------------ > *De :* Pierre Béland <[email protected]> > *À :* Markware Software Services <[email protected]> > *Cc :* HOT Openstreetmap <[email protected]>; S Volk < > [email protected]> > *Envoyé le :* Jeudi 22 janvier 2015 22h30 > *Objet :* Re: [HOT] Damage evaluation tagging schema > > Hi Mark > > I agree, we have to consider also aspects like how easy to extract for an > event. For Haiyan, we had a specific tag. But what, if it would have be > necessary to add tags recently for Hagupit? > > About SQL queries, are-they any efficient way (time related) to say > select objects where key contains "haiyan" ? > > Pierre > >
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