[Qgis-user] alternatives to join attributes

[Albin Blaschka]

Am 17.12.2009 15:46, schrieb Carbonari, Katie (IS):
> Good morning. I have a lot of data I need to visualize in QGIS (142 time
> steps, each with over 200,000 points). I need a way to quickly and
> easily load this data in QGIS. All of my data is in separate .csv files
> (one file per time step). I load each file via the csv plug-in and then
> use join attributes to connect my csv data to the polygon data that
> defines my grid. Join attributes takes forever (trying to do 4,000
> points took an hour). Any one know of any other, faster way to do this?
> Or a way to speed up my join attributes? I know 200,000 points is a lot
> to ask and can easily cut that down a bit, but an hour to do 4000 points
> seems very slow. At that rate, it would take 3 weeks to load the entire
> time series into QGIS. I'm running the latest version of QGIS (Mimas) on
> a Mac OsX.

Good afternoon ;-)

I think with this amount of data is would be the best method to work 
with a spatially enhanced database - most prominently PostgreSQL/PostGIS 
and to do all the datamanagement there - that is the reason why 
databases exist...

So,
1. export your polygon data to Postgres/PostGIS
2. push your csv data also into the database
3. create the necessary objects as tables from point 1+2
4. map it in qgis

The same applies if you do it with spatiallite, which is also possible, 
but with that databasesystem I have no expierence...

Hope this helps,
greetings,
Albin

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