Rails rake db：创建不起作用

Question

大家好！我在为我的 rails 应用程序设置 MySQL 数据库时遇到问题。以下是我的 database.yml 文件的内容：

development:
  adapter: mysql
  encoding: utf8
  reconnect: false
  database: app_name_dev
  pool: 5
  username: root
  password:
  socket: /tmp/mysql.sock


# 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: mysql
  encoding: utf8
  reconnect: false
  database: app_name_test
  pool: 5
  username: root
  password:
  socket: /tmp/mysql.sock


production:
  adapter: mysql
  encoding: utf8
  reconnect: false
  database: app_name_pro
  pool: 5
  username: root
  password:
  socket: /tmp/mysql.sock

我还在我的 gemfile 中将 gem sqlite3 替换为 gem mysql 并运行 bundle install。现在我第一次尝试使用rake db:create 创建数据库。我收到以下错误：

$ rake db:create --trace
(in c:/Users/Kvass/documents/programming/ruby/app_name)
** Invoke db:create (first_time)
** Invoke db:load_config (first_time)
** Invoke rails_env (first_time)
** Execute rails_env
** Execute db:load_config
rake aborted!
couldn't parse YAML at line 1 column 0
c:/Ruby192/lib/ruby/1.9.1/psych.rb:148:in `parse'
c:/Ruby192/lib/ruby/1.9.1/psych.rb:148:in `parse_stream'
c:/Ruby192/lib/ruby/1.9.1/psych.rb:119:in `parse'
c:/Ruby192/lib/ruby/1.9.1/psych.rb:106:in `load'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.7/lib/rails/application/configu
ration.rb:88:in `database_configuration'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/activerecord-3.0.7/lib/active_record/railtie
s/databases.rake:4:in `block (2 levels) in <top (required)>'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:636:in `call'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:636:in `block in exec
ute'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:631:in `each'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:631:in `execute'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:597:in `block in invo
ke_with_call_chain'
c:/Ruby192/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:590:in `invoke_with_c
all_chain'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:607:in `block in invo
ke_prerequisites'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:604:in `each'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:604:in `invoke_prereq
uisites'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:596:in `block in invo
ke_with_call_chain'
c:/Ruby192/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:590:in `invoke_with_c
all_chain'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:583:in `invoke'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:2051:in `invoke_task'

c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:2029:in `block (2 lev
els) in top_level'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:2029:in `each'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:2029:in `block in top
_level'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exc
eption_handling'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:2023:in `top_level'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:2001:in `block in run
'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exc
eption_handling'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/lib/rake.rb:1998:in `run'
c:/Ruby192/lib/ruby/gems/1.9.1/gems/rake-0.8.7/bin/rake:31:in `<top (required)>'

c:/Ruby192/bin/rake:19:in `load'
c:/Ruby192/bin/rake:19:in `<main>'

谁能解释一下我做错了什么？谢谢！

Answer 1

当我尝试运行rake db:create 时，MySQL 服务器尚未在我的机器上运行。粗心的错误：P

Answer 2

尝试将其用作您的 database.yml：

# SQLite version 3.x
#   gem install sqlite3-ruby (not necessary on OS X Leopard)
development:
  adapter: sqlite3
  database: db/development.sqlite3
  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: &TEST
  adapter: sqlite3
  database: db/test.sqlite3
  pool: 5
  timeout: 5000

production:
  adapter: sqlite3
  database: db/production.sqlite3
  pool: 5
  timeout: 5000

cucumber:
  <<: *TEST

Answer 3

在我的开发过程中，我使用这个配置：

development:
    adapter: mysql2
    database: my_db
    encoding: utf8
    username: rails
    password: rails
    host: localhost