手元で簡易なテスト用PostgreSQL環境作る手順を簡単にまとめておきます。

DockerでPostgreSQLサービス起動：

$ docker run --name postgres -d -p 5432:5432 postgres

コンテナーの中に入る：

$ docker exec -it postgres bash

psqlでユーザとデータベースを作る：

# su - postgres
No directory, logging in with HOME=/

$ psql  
psql (9.5.4)
Type "help" for help.

postgres=# \du
                                   List of roles
 Role name |                         Attributes                         | Member of 
-----------+------------------------------------------------------------+-----------
 postgres  | Superuser, Create role, Create DB, Replication, Bypass RLS | {}

postgres=# CREATE ROLE foobar LOGIN CREATEDB PASSWORD 'foobar';
CREATE ROLE

postgres=# \du
                                   List of roles
 Role name |                         Attributes                         | Member of 
-----------+------------------------------------------------------------+-----------
 postgres  | Superuser, Create role, Create DB, Replication, Bypass RLS | {}
 foobar      | Create DB                                                  | {}

postgres=# CREATE DATABASE foobar OWNER foobar;
CREATE DATABASE