Pick your elephant poison

There are a myriad of ways to install PostgreSQL on a Mac. I will be going over brew and Postgres.app. I like to go with the app as it eases into my workflow but does require it’s path to be set in your profile (e.g .zshrc, .bashrc, or fish.config)

Homebrew Installation

The homebrew installation is straightforward and can be done by following the guide below.

  • Run a brew command to install PG and take note of the documentation that follows it.
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brew install postgresql
  • If this is your first install run the following command to create your first database
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initdb /usr/local/var/postgres -E utf8
  • Create aliases to simplify the start and stop of the Postgres service
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alias pg-start='pg_ctl -D /usr/local/var/postgres -l /usr/local/var/postgres/server.log start'
alias pg-stop='pg_ctl -D /usr/local/var/postgres stop -s -m fast'

Postgres.app Installation

  1. Visit http://postgresapp.com
  2. Download the latest version which as of this writing is 9.2.4.1
  3. Drag, drop, and open the elephant icon into the Application folder.
  4. Set the following in your .bashrc or.zshrc

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     PATH="/Applications/Postgres.app/Contents/MacOS/bin:$PATH"
     # If you are using Fish, use the following:
     set PATH /Applications/Postgres.app/Contents/MacOS/bin $PATH
    
  5. Open the elephant and verify it is referencing the app using which psql

The path should look like what was entered above but if all else fails restart your terminal session.

Use Postgres in Rails

Now that you’ve successfully installed PG, you can utilize it in rails by including it in your gemfile.

New Rails App

If you have yet to generate your rails app, you can set Postgresql as your database by running rails new blog -d postgresql You will then have to run rake db:create:all to create the databases in the database.yml file.

Existing Rails App

For an existing rails app you will need to add the pg gem to your gemfile like so.

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source 'https://rubygems.org'

gem 'rails', '4.0.0.rc1'
gem "pg", "~> 0.15.1"

gem 'sass-rails', '~> 4.0.0.rc1'
gem 'uglifier', '>= 1.3.0'
gem 'coffee-rails', '~> 4.0.0'
gem 'jquery-rails'
gem 'turbolinks'

You will also need to change your database.yml file to look something like this:

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development:
  adapter: postgresql
  encoding: utf8
  database: blog_dev
  host: localhost
test:
  adapter: postgresql
  encoding: utf8
  database: blog_test
  host: localhost

production:
  adapter: postgresql
  encoding: utf8
  database: blog_production
  host: supersecretserver

Finally, you can run rake db:create:all followed by rake db:migrate and continue editing your amazing rails app!

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