0
我在用mysql數據庫支持的rails上創建一個新的應用程序。但是，當我嘗試運行應用程序，它崩潰，出現以下錯誤信息：Ruby on Rails應用程序支持MySQL數據庫在Heroku上崩潰並顯示錯誤消息
Running `rails console` attached to terminal... up, run.1388
/app/vendor/bundle/ruby/2.0.0/gems/activerecord-4.2.3/lib/active_record/connection_adapters/connection_specification.rb:177:in `rescue in spec': Specified 'postgresql' for database adapter, but the gem is not loaded. Add `gem 'pg'` to your Gemfile (and ensure its version is at the minimum required by ActiveRecord). (Gem::LoadError)
from /app/vendor/bundle/ruby/2.0.0/gems/activerecord-4.2.3/lib/active_record/connection_adapters/connection_specification.rb:174:in `spec'
from /app/vendor/bundle/ruby/2.0.0/gems/activerecord-4.2.3/lib/active_record/connection_handling.rb:50:in `establish_connection'
from /app/vendor/bundle/ruby/2.0.0/gems/activerecord-4.2.3/lib/active_record/railtie.rb:120:in `block (2 levels) in <class:Railtie>'
from /app/vendor/bundle/ruby/2.0.0/gems/activesupport-4.2.3/lib/active_support/lazy_load_hooks.rb:38:in `instance_eval'
from /app/vendor/bundle/ruby/2.0.0/gems/activesupport-4.2.3/lib/active_support/lazy_load_hooks.rb:38:in `execute_hook'
from /app/vendor/bundle/ruby/2.0.0/gems/activesupport-4.2.3/lib/active_support/lazy_load_hooks.rb:45:in `block in run_load_hooks'
from /app/vendor/bundle/ruby/2.0.0/gems/activesupport-4.2.3/lib/active_support/lazy_load_hooks.rb:44:in `each'
from /app/vendor/bundle/ruby/2.0.0/gems/activesupport-4.2.3/lib/active_support/lazy_load_hooks.rb:44:in `run_load_hooks'
from /app/vendor/bundle/ruby/2.0.0/gems/activerecord-4.2.3/lib/active_record/base.rb:315:in `<module:ActiveRecord>'
from /app/vendor/bundle/ruby/2.0.0/gems/activerecord-4.2.3/lib/active_record/base.rb:26:in `<top (required)>'
from /app/vendor/bundle/ruby/2.0.0/gems/activerecord-4.2.3/lib/active_record/relation/predicate_builder.rb:121:in `<class:PredicateBuilder>'
from /app/vendor/bundle/ruby/2.0.0/gems/activerecord-4.2.3/lib/active_record/relation/predicate_builder.rb:2:in `<module:ActiveRecord>'
from /app/vendor/bundle/ruby/2.0.0/gems/activerecord-4.2.3/lib/active_record/relation/predicate_builder.rb:1:in `<top (required)>'
from /app/vendor/bundle/ruby/2.0.0/gems/activesupport-4.2.3/lib/active_support/dependencies.rb:274:in `require'
from /app/vendor/bundle/ruby/2.0.0/gems/activesupport-4.2.3/lib/active_support/dependencies.rb:274:in `block in require'
from /app/vendor/bundle/ruby/2.0.0/gems/activesupport-4.2.3/lib/active_support/dependencies.rb:240:in `load_dependency'
from /app/vendor/bundle/ruby/2.0.0/gems/activesupport-4.2.3/lib/active_support/dependencies.rb:274:in `require'
from /app/vendor/bundle/ruby/2.0.0/gems/activesupport-4.2.3/lib/active_support/dependencies/autoload.rb:70:in `block in eager_load!'
from /app/vendor/bundle/ruby/2.0.0/gems/activesupport-4.2.3/lib/active_support/dependencies/autoload.rb:70:in `each_value'
from /app/vendor/bundle/ruby/2.0.0/gems/activesupport-4.2.3/lib/active_support/dependencies/autoload.rb:70:in `eager_load!'
from /app/vendor/bundle/ruby/2.0.0/gems/activerecord-4.2.3/lib/active_record.rb:159:in `eager_load!'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/application/finisher.rb:56:in `each'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/application/finisher.rb:56:in `block in <module:Finisher>'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/initializable.rb:30:in `instance_exec'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/initializable.rb:30:in `run'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/initializable.rb:55:in `block in run_initializers'
from /app/vendor/ruby-2.0.0/lib/ruby/2.0.0/tsort.rb:150:in `block in tsort_each'
from /app/vendor/ruby-2.0.0/lib/ruby/2.0.0/tsort.rb:183:in `block (2 levels) in each_strongly_connected_component'
from /app/vendor/ruby-2.0.0/lib/ruby/2.0.0/tsort.rb:219:in `each_strongly_connected_component_from'
from /app/vendor/ruby-2.0.0/lib/ruby/2.0.0/tsort.rb:182:in `block in each_strongly_connected_component'
from /app/vendor/ruby-2.0.0/lib/ruby/2.0.0/tsort.rb:180:in `each'
from /app/vendor/ruby-2.0.0/lib/ruby/2.0.0/tsort.rb:180:in `each_strongly_connected_component'
from /app/vendor/ruby-2.0.0/lib/ruby/2.0.0/tsort.rb:148:in `tsort_each'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/initializable.rb:54:in `run_initializers'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/application.rb:352:in `initialize!'
from /app/config/environment.rb:5:in `<top (required)>'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/application.rb:328:in `require'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/application.rb:328:in `require_environment!'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/commands/commands_tasks.rb:142:in `require_application_and_environment!'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/commands/commands_tasks.rb:67:in `console'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
from /app/vendor/bundle/ruby/2.0.0/gems/railties-4.2.3/lib/rails/commands.rb:17:in `<top (required)>'
from /app/bin/rails:8:in `require'
from /app/bin/rails:8:in `<main>'
我不明白，錯誤本身的第一道防線。我將應用程序配置爲在MySQL數據庫上運行，但它指定了PostgreSQL。我是一個新手，你能幫我調試我的應用程序。這只是被命令創建一個基本的應用程序：
rails new myFirstApplication
沒有更改向它提出的。 這裏是一個被配置到MySQL使用我的database.yml文件：
default: &default
adapter: mysql2
encoding: utf8
pool: 5
username: root
password: 80517326A!
socket: /var/run/mysqld/mysqld.sock
development:
<<: *default
database: myFirstApplication_development
test:
<<: *default
database: myFirstApplication_test
production:
<<: *default
database: myFirstApplication_production
username: myFirstApplication
password: <%= ENV['MYFIRSTAPPLICATION_DATABASE_PASSWORD'] %>
Heroku不適用於mysql，它只適用於postgres。 – BroiSatse
@BroiSatse哦，我明白了！是否有可能在開發環境中使用MySQL，但在生產環境中（即在Heroku中）使用PostgreSQL？如果是這樣，怎麼樣？ –
你可以做到這一點，但我不會推薦這一點--MySQL在很多方面的表現與PostgreSQL不同，並且在開發中可能無法在生產中使用。 – BroiSatse