Setting up a Postgres Database for Rails (but not necessarily)

Created: 2023-02-09

This is geared toward debian linux users.

Connecting to Postgres and looking around.

Log into your postgres instance with sudo -u postgres psql
You should see the psql prompt

~/repos/chorelist$ sudo -u postgres psql
psql (14.6 (Ubuntu 14.6-0ubuntu0.22.04.1))
Type "help" for help.

postgres=#

\?: list of possible commands and short descriptions. This should be in a less-type interface. This means you can search with / followed by your search term.
\l: list current databases.
\du: list roles (aka users) and their permissions.
\q: exits the postgres interface.

Setting up a New User

Connect to your database as mentioned above.
create user username with encrypted password 'password'; creates the user.
Since Rails does the all the lifting all our user needs is the create database attribute, alter user username CREATEDB;

Setting up Rails

At this point you need to set up your application so that it can connect to the database.

add the pg gem to your Gemfile (e.g. gem "pg")
update config\database.yml to look something like this.

default: &default
  adapter: postgresql
  encoding: unicode
  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
  username: db_username
  password: db_password 
  timeout: 5000

development:
  <<: *default
  database: app_development
  host: localhost

test:
  <<: *default
  database: app_test
  host: localhost

# Omitting the production section as that will vary on your deployment setup.

Run bundle exec rails db:create, and rails will create your development and test databases if you did everything correctly.
You can log back into psql and use the \l to see if those databases are now listed.

Back