The first step is to remove older version of PostGIS if any.
sudo apt-get purge postgis
wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -
sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt/ trusty-pgdg main" >> /etc/apt/sources.list.d/postgresql.list'
sudo apt-get update && sudo apt-get install postgresql-9.4-postgis-2.1 -f
Now, let’s see how we can create a PostGIS enabled database. We have two ways of doing this, in which the first one is the latest and simple one:
This is as simple as running a query in the database where you want to enable PostGIS:
CREATE EXTENSION postgis;
OR
This is an old method of doing the same. Creating a template for PostGIS will make it easy to enable PostGIS for every new database you create:
createdb -E UTF8 template_postgis2.1
psql -d postgres -c "UPDATE pg_database SET datistemplate='true' WHERE datname='template_postgis2.1'"
Now, we have to run an SQL script comes along with PostGIS in the template:
psql -d template_postgis2.1 -f /usr/share/postgresql/9.4/extension/postgis--2.1.5.sql
psql -d template_postgis2.1 -c "GRANT ALL ON geometry_columns TO PUBLIC;"
psql -d template_postgis2.1 -c "GRANT ALL ON geography_columns TO PUBLIC;"
psql -d template_postgis2.1 -c "GRANT ALL ON spatial_ref_sys TO PUBLIC;"
Let’s test the PostGIS installation by creating a test database:
createdb test_db -T template_postgis2.1
In test_db you can run the following statement to make sure that you installed and configured PostGIS correctly:
test_db=# select postgis_version();
postgis_version---------------------------------------
2.1 USE_GEOS=1 USE_PROJ=1 USE_STATS=1
(1 row)
If you don’t want to use the CREATE EXTENSION
statement and want to enable PostGIS for an already existing database. It is simple enough, you just need to run the PostGIS 2.1 script in your database:
psql -d test_db -f /usr/share/postgresql/9.4/extension/postgis--2.1.5.sql
inspiration http://technobytz.com/install-postgis-postgresql-9-3-ubuntu.html