The steps you need to follow to complete this recipe are as follows:
- In case you still haven't done it, export the countries shapefile to PostGIS using the ogr2ogr or the shp2pgsql commands. The shp2pgsql approach is as shown:
$ shp2pgsql -I -d -s 4326 -W LATIN1 -g the_geom countries.shp chp01.countries > countries.sql $ psql -U me -d postgis_cookbook -f countries.sql
- The ogr2ogr approach is as follows:
$ ogr2ogr -f PostgreSQL PG:"dbname='postgis_cookbook' user='me' password='mypassword'" -lco SCHEMA=chp01 countries.shp -nlt MULTIPOLYGON -lco OVERWRITE=YES -lco GEOMETRY_NAME=the_geom
- Now, query PostGIS in order to get a list of countries grouped by the subregion field. For this purpose, you will merge the geometries ...