[OSM-dev] Lite OSM backend

Dean Earley dean at earlsoft.co.uk
Fri Sep 8 11:56:41 BST 2006


Nicola Ranaldo wrote:
> I'm thinking about storing osm data in a lite database backend for general 
> client software usage and to begin a binary distribution of planet.osm (last 
> import started at 12.00 this morning and is not yet finished).
> As last discussions was projected in coordinating developing jobs, i think we 
> should talk about this idea before someone (me?) begin to write some code!
> We could start in choosing between BerkleyDB or SQLite.. or some other 
> backends focusing on speed  and memory usage, in order to get it usable on 
> handhelds devices.

I'm currently using SQLite (2.8) as a binary backend but...
The 3GB XML generates a 3.8GB database file WITHOUT indexes on the node 
positions.
I am looking to move to SQLite 3.0 which actually stores the numerical 
data as numbers rather than text which should give me a 40% decrease.

I did a test of copying just the UK data and it came out at 1.8GB with 
indexes but that does include all the way data (I haven't figured out 
how to filter that yet :)

One potential issue I see with your format is lack of indexes which will 
be required for any large dataset.

-- 
Dean Earley, Dee (dean at earlsoft.co.uk)

irc:    irc://irc.blitzed.org/
web:    http://personal.earlsoft.co.uk
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