I am running Ubuntu 10.04, Rails 3.0.7, Ruby 1.9.2

I started with this link: Convert a Ruby on Rails app from sqlite to MySQL?

I successfully installed 'mysql2'

database.yml :

# SQLite version 3.x
#   gem install sqlite3
development:
  adapter: mysql2
  database: db/development.mysql2
  pool: 5
  timeout: 5000 
# Warning: The database defined as "test" will be erased and
# re-generated from your development database when you run "rake".
# Do not set this db to the same as development or production.
test:
  adapter: mysql2
  database: db/test.mysql2
  pool: 5
  timeout: 5000

production:
  adapter: mysql2
  database: db/production.mysql2
  pool: 5
  timeout: 5000

When i get to step 5 :

rake db:create

I get this error (with trace):

** Invoke db:create (first_time)

** Invoke db:load_config (first_time)

** Invoke rails_env (first_time)

** Execute rails_env

** Execute db:load_config

** Execute db:create

Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)

Couldn't create database for {"adapter"=>"mysql2", "database"=>"db/test.mysql2", 
"pool"=>5, "timeou开发者_如何转开发t"=>5000}, charset: utf8, collation: utf8_unicode_ci

Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)

Couldn't create database for {"adapter"=>"mysql2", "database"=>"db/development.mysql2", 
"pool"=>5, "timeout"=>5000}, charset: utf8, collation: utf8_unicode_ci

Any suggestions?

The problem is that you haven't started your MySQL server yet, so it's failing to create the database because the server is having the common mysqld.sock error.

Here's a fantastic resource for this: http://matthom.com/archive/2009/06/14/installing-mysql-mac-os-x

On my machine, it works when I start at 'Connecting to MySQL', but there are a couple of other sections explaining alternative resolutions to the socket error.