[postgis-users] Spatially ordering data

[Travis Kirstine]

if you go with Remi suggestion you then can cluster the quad tree index to
reorder records

http://postgis.net/docs/performance_tips.html



On 1 March 2017 at 07:11, Rémi Cura <remi.cura at gmail.com> wrote:

> hey,
> the most classical approach would be to construct a quad tree
> <https://en.wikipedia.org/wiki/Quadtree>.
> You can think of it as a grid that adapts its resolution locally according
> to the data.
> This is also easy to code.
>
> Cheers,
> Rémi-C
>
> 2017-03-01 12:46 GMT+01:00 Darafei "Komяpa" Praliaskouski <me at komzpa.net>:
>
>> Have a look here:
>>
>> http://www.paulnorman.ca/blog/2016/05/improve-your-st-geohas
>> h-sorting-with-these-three-simple-tricks/
>>
>> for simplest case, you can just order by your geom field.
>>
>> ср, 1 мар. 2017 г. в 14:44, Jonathan Moules <jonathan-lists at lightpear.com
>> >:
>>
>>> Hi List,
>>> I've got a database of about 60 million spatial features that I need to
>>> run through a process.
>>>
>>> The process can't do all of them at once, so I want to get the data from
>>> postgis in spatial chunks of up to say 500,000 features per query.
>>>
>>> The data itself isn't evenly spatially distributed, so gridding won't
>>> work either, and I don't see any prospectively useful functions in the
>>> reference.
>>>
>>> Non-spatially this would be simple:
>>>
>>>     *SELECT * FROM my_table ORDER BY some_key ASC LIMIT 500000 OFFSET 0*
>>>
>>> Does anyone have any suggestions for how to spatially order data with
>>> PostGIS?
>>>
>>> Thanks,
>>> Jonathan
>>> _______________________________________________
>>> postgis-users mailing list
>>> postgis-users at lists.osgeo.org
>>> https://lists.osgeo.org/mailman/listinfo/postgis-users
>>
>>
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>
>
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