Postgres No permission to create user

Question

I am unable to use rails with postgres. The database wont create:

sayth@sayth-TravelMate-5740G:~/testapp2$ rake db:create:all
PG::InsufficientPrivilege: ERROR:  permission denied to create database
: CREATE DATABASE "testapp2_development" ENCODING = 'unicode'
....
Couldn't create database for {"adapter"=>"postgresql", "encoding"=>"unicode", "database"=>"testapp2_production", "pool"=>5, "username"=>"testapp2", "password"=>nil}

So I am following the solution here https://stackoverflow.com/a/8639649

These are the steps i am having issue with.

$ psql -d postgres
postgres=# create role app_name login createdb;
postgres=# \q

However when I am in the psql shell to give the create role with createdb ability it fails auth.

sayth@sayth-TravelMate-5740G:~/testapp2$ psql -d postgres
psql (9.2.4)
Type "help" for help.

postgres=> create role sayth createdb;
ERROR:  permission denied to create role
postgres=> 

How then do I create the auth?

Edit Update Reviewing http://www.postgresql.org/docs/9.2/static/tutorial-createdb.html And http://www.postgresql.org/docs/9.2/static/database-roles.html

But cannot use root to create accounts as it doesn't exist and I need to be root to create it.

sayth@sayth-TravelMate-5740G:~$ sudo psql -d postgres
[sudo] password for sayth: 
Sorry, try again.
[sudo] password for sayth: 
psql: FATAL:  role "root" does not exist

Answer 1

Add this using during gitlab_ci DB setup. I solve the problem as described by @Audrius Meškauskas on Ubuntu 12.04:

Connect as Admin

sudo -u postgres psql -d template1

Alter role

ALTER ROLE gitlab_ci WITH CREATEDB;

Re-run the task

sudo -u gitlab_ci -H bundle exec rake db:setup RAILS_ENV=production