[postgis-users] Append only new features

[Stephen Woodbridge]

brizey02 wrote:
> I am trying to load the combined
> http://www.weather.gov/regsci/gis/shapefiles/allwarn.zip but I only want to
> load the new warnings is there a way to load only the new geometries? I was
> doing a append but there were warnings being duplicated until they expired,
> I know there are 3 unique identifiers WFO, TYPE,ETN is there a way to load
> only the new ones?

It seems like the answer to this is based in the answer to the 
definition of how to define a "new warning".

shp2pgsql is just a bulk loader, so load the data into a alternate 
table, then run a query to identify the new records and insert them into 
your existing table. Then drop the alternate working table.

-Steve