title: How can I activate the unaccent extension on an already existing model
body: <p>When I try to install the <code>unaccent</code> Postgres extension (through the <code>postgresql-contrib</code> package), everything works as per the below:</p>
  
  <pre><code># psql -U postgres -W -h localhost
  Password for user postgres:
  psql (9.3.9)
  SSL connection (cipher: DHE-RSA-AES256-GCM-SHA384, bits: 256)
  Type "help" for help.
  
  postgres=# CREATE EXTENSION unaccent;
  CREATE EXTENSION
  postgres=# SELECT unaccent('Hélène');
   unaccent
  ----------
   Helene
  (1 row)
  </code></pre>
  
  <p>However, when I try to use with Django 1.8, I get following error:</p>
  
  <pre><code>ProgrammingError: function unaccent(character varying) does not exist
  LINE 1: ...able" WHERE ("my_table"."live" = true AND UNACCENT("...
                                                               ^
  HINT:  No function matches the given name and argument types. You might need to add explicit type casts.
  </code></pre>
  
  <p>Using Postgresql 9.3 and Django 1.8.</p>