Re: [Talk-in] [datameet] How does OSM store its data

2018-02-04 Thread Sajjad Anwar
Hey Nikhil,

OSM uses a PostgreSQL database as the main data store, along with PostGIS
extension for geometries. The tags are stored in key and value columns and
uses hstore, which makes it easy to add new ones without having to modify
the table schema. You can read about the database schema and infrastructure
here https://wiki.openstreetmap.org/wiki/Database

Overpass is independent of the above infrastructure. It reads from the
replication files and builds a binary on-disk database. More about Overpass
here https://wiki.openstreetmap.org/wiki/Overpass_API

Also, you should join the OSM Talk-in mailing list if you haven't!
https://lists.openstreetmap.org/listinfo/talk-in

Sajjad

On Mon, Feb 5, 2018 at 11:12 AM, Nikhil VJ  wrote:

> Hi,
>
> I want to learn how OpenStreetmap stores and manages its data, plus how
> Overpass Turbo extracts it.
>
> I find the key-value pair system fascinating (variable fields, organic
> building up of data) and want to replicate that elsewhere. Just the data
> storing part.. don't want to generate map tiles etc.
>
> Any pointers? Any place I should ask?
>
> For those interested, here's a link to the project I have in mind:
> Crowdsourcing-Map-based-data
> 
>
> --
> Cheers,
> Nikhil VJ
> Pune, India
>
> --
> Datameet is a community of Data Science enthusiasts in India. Know more
> about us by visiting http://datameet.org
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Re: [Talk-in] [datameet] How does OSM store its data

2018-02-04 Thread Devdatta Tengshe
Hi Nikhil,

The Database design has been documented here:
https://wiki.openstreetmap.org/wiki/Database

This is, at its essence, a modified EAV Model(
https://en.wikipedia.org/wiki/Entity–attribute–value_model). A good place
to start researching for these kinds of database design, is to look at
various documents on EAV, its shortcomings & Strengths.

You should also evaluate if a NoSQL/Object Store database might be a better
fit for your purpose, than designing an EAV Data model to be stored in a
relational Database.


Regards,
Devdatta

On Mon, Feb 5, 2018 at 11:12 AM, Nikhil VJ  wrote:

> Hi,
>
> I want to learn how OpenStreetmap stores and manages its data, plus how
> Overpass Turbo extracts it.
>
> I find the key-value pair system fascinating (variable fields, organic
> building up of data) and want to replicate that elsewhere. Just the data
> storing part.. don't want to generate map tiles etc.
>
> Any pointers? Any place I should ask?
>
> For those interested, here's a link to the project I have in mind:
> Crowdsourcing-Map-based-data
> 
>
> --
> Cheers,
> Nikhil VJ
> Pune, India
>
> --
> Datameet is a community of Data Science enthusiasts in India. Know more
> about us by visiting http://datameet.org
> ---
> You received this message because you are subscribed to the Google Groups
> "datameet" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to datameet+unsubscr...@googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.
>
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