PostgreSQL error 'Could not connect to server: No such file or directory'

Question

Like some others I am getting this error when I run rake db:migrate in my project or even try most database tasks for my Ruby on Rails 3.2 applications.

Answer 1

If you are running Homebrew, uninstall Postgresql end pg gems:*

$ gem uninstall pg
$ brew uninstall postgresql

Download and run the following script to fix permission on /usr/local:* https://gist.github.com/rpavlik/768518

$ ruby fix_homebrew.rb

Then install Postgres again and pg gem:*

$ brew install postgresql  
$ initdb /usr/local/var/postgres -E utf8

To have launchd start postgresql at login run:

$ ln -sfv /usr/local/opt/postgresql/*.plist ~/Library/LaunchAgents 

Or start manually.

Install pg gem

$ gem install pg

I hope have helped