Postgis install [closed]

I have Postgres version 8.4.8

select version();
PostgreSQL 8.4.8 on i686-pc-linux-gnu, compiled by GCC gcc-4.4.real (Ubuntu/Linaro 4.4.4-14ubuntu5) 4.4.5, 32-bit

Installed Postgis via the synaptic package manager, (postgis and postgresql-8.4-postgis) everything seemed to go fine. Then when I try to verify the Postgis version, things are not fine. Both of these give the same error.

SELECT PostGIS_version();
SELECT PostGIS_full_version();

ERROR:  function postgis_full_version() does not exist
LINE 1: SELECT PostGIS_full_version();
HINT:  No function matches the given name and argument types. You might need to add explicit type casts.

The package manager claims Postgis is installed. How can I verify that the install worked or didn't work ?

PostGIS needs to be installed per database. Existing databases are not altered automatically. Run the install script as follows.

In PostgreSQL 8.4 you may also need to create the language plpgsql. For 9.0+ it is the default procedural language and installed automatically. In your database:

createlang plpgsql yourdatabase

Can't do harm. If plpgsql is already installed it will just yield an error telling you so. Go to the install dir. In Debian Squeeze the contrib packages lie here (may be different in Ubuntu). In a shell:

cd /usr/share/postgresql/8.4/contrib/postgis-1.5

Then execute (as postgres user or you have to provide username / pw):

psql -d yourdatabase -f postgis.sql
psql -d yourdatabase -f spatial_ref_sys.sql

You may also want to install the comments to your shiny new functions (optional). In Debian Squeeze the install file lies in the /contrib main directory:

cd /usr/share/postgresql/8.4/contrib
psql -d yourdatabase -f postgis_comments.sql

If you want PostGIS to be installed with every new database in the cluster by default, install it to your template1 database also. Read more about that in the manual.

Sources for PostGIS installation (on Ubuntu):

http://postgis.net/docs/manual-2.1/postgis_installation.html
http://www.paolocorti.net/2008/01/30/installing-postgis-on-ubuntu/

PostgreSQL 9.1+

With PostgreSQL 9.1 or newer you can use the more convenient CREATE EXTENSION:

CREATE EXTENSION postgis;
CREATE EXTENSION postgis_topology;

Your distribution is probably shipping the extension ready for installation. If not, consider the chapter "Building PostGIS Extensions and Deploying them" in the PostGIS manual.