[osmosis-dev] Osmosis use case

[Peter Körner]

> From a data modeling perspective - and I'm on somewhat thin ice here, 
> happy for anyone to chip in and confirm or protest - the APIDB schema is 
> the most powerful because it has all the data plus history. The "Simple" 
> schema, as well as the Osm2pgsql slim-mode schema, still have a full OSM 
> data snapshot (and you could theoretically convert from one to the 
> other, or from APIDB into one of them) but they don't have history.
That's not fully true, i think. osm2pgsql reduces the saved tags to 
those mentioned in the import-style-file, so it drops information that 
is not needed for the rendering process (eg. "source" and "description" 
tags). This is true for non-slim- as well as for slim-mode

There is a very new, third osm2pgsql variety using the postgres 
hstore-new plugin. This database style saves all tags and all values and 
allows very fast, indexed searches on them. It's really new (we're 
currently importing our first planet!) but we already played around with 
country-extracts.

Peter