Ruby on Rails MYSQL错误用户’root @ localhost’访问被拒绝
使用新应用启动rails服务器时出现以下错误：
/Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/mysql2-0.2.6/lib/mysql2/client.rb:37:in`connect’：用户’root’@’拒绝访问localhost’（使用密码：YES）（Mysql2 :: Error）
这是我的database.yml
# MySQL. Versions 4.1 and 5.0 are recommended. # # Install the MySQL driver: # gem install mysql2 # # And be sure to use new-style password hashing: # http://dev.mysql.com/doc/refman/5.0/en/old-client.html development: adapter: mysql2 encoding: utf8 reconnect: false database: group_chat_development pool: 5 username: root password: admin 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: mysql2 encoding: utf8 reconnect: false database: group_chat_test pool: 5 username: root password: admin socket: /tmp/mysql.sock production: adapter: mysql2 encoding: utf8 reconnect: false database: group_chat_production pool: 5 username: root password: admin socket: /tmp/mysql.sock 以下是完整的错误消息
MacPro:FireDemon fred$ rails s => Booting Mongrel => Rails 3.0.3 application starting in development on http://0.0.0.0:3000 => Call with -d to detach => Ctrl-C to shutdown server Exiting /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/mysql2-0.2.6/lib/mysql2/client.rb:37:in `connect': Access denied for user 'root'@'localhost' (using password: YES) (Mysql2::Error) from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/mysql2-0.2.6/lib/mysql2/client.rb:37:in `initialize' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/mysql2-0.2.6/lib/active_record/connection_adapters/mysql2_adapter.rb:14:in `new' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/mysql2-0.2.6/lib/active_record/connection_adapters/mysql2_adapter.rb:14:in `mysql2_connection' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:228:in `new_connection' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:236:in `checkout_new_connection' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:190:in `block (2 levels) in checkout' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:186:in `loop' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:186:in `block in checkout' from /Users/fred/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:185:in `checkout' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:93:in `connection' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_pool.rb:316:in `retrieve_connection' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_specification.rb:97:in `retrieve_connection' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/connection_adapters/abstract/connection_specification.rb:89:in `connection' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/base.rb:1330:in `replace_bind_variables' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/base.rb:1317:in `sanitize_sql_array' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/base.rb:1224:in `sanitize_sql_for_conditions' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/relation/query_methods.rb:206:in `build_where' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/relation/query_methods.rb:77:in `where' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/base.rb:441:in `where' from /Users/fred/Desktop/FireDemon/app/models/user.rb:14:in `' from /Users/fred/Desktop/FireDemon/app/models/user.rb:1:in `' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:454:in `load' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:454:in `block in load_file' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:596:in `new_constants_in' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:453:in `load_file' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:340:in `require_or_load' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:491:in `load_missing_constant' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:183:in `block in const_missing' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:181:in `each' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:181:in `const_missing' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/inflector/methods.rb:124:in `block in constantize' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/inflector/methods.rb:123:in `each' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/inflector/methods.rb:123:in `constantize' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/core_ext/string/inflections.rb:43:in `constantize' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activemodel-3.0.3/lib/active_model/observing.rb:182:in `observed_class' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activemodel-3.0.3/lib/active_model/observing.rb:175:in `observed_classes' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activemodel-3.0.3/lib/active_model/observing.rb:195:in `observed_classes' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activemodel-3.0.3/lib/active_model/observing.rb:191:in `initialize' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/observer.rb:96:in `initialize' from /Users/fred/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/singleton.rb:109:in `new' from /Users/fred/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/singleton.rb:109:in `block in instance' from :10:in `synchronize' from /Users/fred/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/singleton.rb:107:in `instance' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activemodel-3.0.3/lib/active_model/observing.rb:66:in `instantiate_observer' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activemodel-3.0.3/lib/active_model/observing.rb:39:in `block in instantiate_observers' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activemodel-3.0.3/lib/active_model/observing.rb:39:in `each' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activemodel-3.0.3/lib/active_model/observing.rb:39:in `instantiate_observers' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/railtie.rb:83:in `block (2 levels) in ' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/lazy_load_hooks.rb:36:in `instance_eval' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/lazy_load_hooks.rb:36:in `execute_hook' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/lazy_load_hooks.rb:26:in `on_load' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activerecord-3.0.3/lib/active_record/railtie.rb:82:in `block in ' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/lazy_load_hooks.rb:34:in `call' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/lazy_load_hooks.rb:34:in `execute_hook' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/lazy_load_hooks.rb:43:in `block in run_load_hooks' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/lazy_load_hooks.rb:42:in `each' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/lazy_load_hooks.rb:42:in `run_load_hooks' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.3/lib/rails/application/finisher.rb:46:in `block in ' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.3/lib/rails/initializable.rb:25:in `instance_exec' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.3/lib/rails/initializable.rb:25:in `run' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.3/lib/rails/initializable.rb:50:in `block in run_initializers' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.3/lib/rails/initializable.rb:49:in `each' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.3/lib/rails/initializable.rb:49:in `run_initializers' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.3/lib/rails/application.rb:134:in `initialize!' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.3/lib/rails/application.rb:77:in `method_missing' from /Users/fred/Desktop/FireDemon/config/environment.rb:5:in `' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:239:in `require' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:239:in `block in require' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:225:in `block in load_dependency' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:596:in `new_constants_in' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:225:in `load_dependency' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:239:in `require' from /Users/fred/Desktop/FireDemon/config.ru:3:in `block in ' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/builder.rb:46:in `instance_eval' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/builder.rb:46:in `initialize' from /Users/fred/Desktop/FireDemon/config.ru:1:in `new' from /Users/fred/Desktop/FireDemon/config.ru:1:in `' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/builder.rb:35:in `eval' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/builder.rb:35:in `parse_file' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/server.rb:162:in `app' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/server.rb:248:in `wrapped_app' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/server.rb:213:in `start' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.3/lib/rails/commands/server.rb:65:in `start' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.3/lib/rails/commands.rb:30:in `block in ' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.3/lib/rails/commands.rb:27:in `tap' from /Users/fred/.rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.3/lib/rails/commands.rb:27:in `' from script/rails:6:in `require' from script/rails:6:in `' MacPro:FireDemon fred$
好像您的用户无法连接到MySQL DB。 在控制台中尝试以下命令：
mysql -u root -p
出现提示时，将密码设为“admin”
如果这是可能的，那么你应该好好去。
config/database.yml文件中root用户的密码错误。 如果忘记了root用户的密码，您可以随时使用mysqladmin命令更改root用户的密码。
方便的家庭提示 – 我也被困在这，但发现环回（127.0.0.1）！=’localhost’…我有主机：127.0.0.1，并看到这个确切的问题。 快速更改为’localhost’为我解决了这个问题…希望它有助于某人。
development: adapter: mysql2 database: mydb host: localhost username: root password: mypass
答案在您的问题> MYSQL错误用户’root @ localhost’拒绝访问
将具有管理员密码的root用户应用于group_chat_development MySQL数据库
更新我发现您可能不希望在您的开发和测试数据库中使用msQL，在这种情况下将您的database.yml文件测试和开发设置更改为
# 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: adapter: sqlite3 database: db/test.sqlite3 pool: 5 timeout: 5000
如果您不知道如何使用MySQL工具，那么您应该很快习惯使用它们，因为您很可能在生产服务器环境中需要它们您将在此处找到您在MySQL上使用的相关版本的链接http：/ /dev.mysql.com/doc/使用MySQL Administrator设置用户权限。
如果您是第一次设置mysql root密码，请键入以下命令，如下所示：
mysqladmin密码
系统将提示您输入新密码并确认密码。
确认后，尝试使用刚刚设置的用户root和密码登录。
mysql root @’你的新密码’
注意：您必须以root用户身份登录，然后才能设置mysql密码。
谢谢。
所以我被困了一段时间。
检查文件config / database.yml并检查您的设置。
default: &default adapter: mysql2 encoding: utf8 pool: 5 username: root password: root socket: ( check what your socket location is by typing mysqladmin version into termnal)
然后进入终端并输入
mysql -u root -p
然后，最后关闭终端并重新打开它
bundle instal
然后
rails s
它接缝就像你必须再次捆绑安装才能进行更改。
希望有所帮助！
对我来说，它通过定义用户名来解决，而不是留空
development: adapter: mysql2 database: my_db encoding: utf8 username: # ADD DATABASE USERNAME password: # ADD DATABASE PASSWORD host: localhost
所以我只需将所有数据库的更改为以下内容
development: adapter: mysql2 database: my_db encoding: utf8 username: root password: # ADD DATABASE PASSWORD host: localhost
它工作正常，希望这会有所帮助
你应该在database.yml文件的devlepment中给出“host：”字段。 那个主机名必须是“IP”地址，比如“127.0.0.1”或者某些东西..即“主机：127.0.0.1”并再次重新启动服务器并输入地址如“127.0.0.1:3000”这里3000是港口提名者……
如果您使用oracle软件包安装，请尝试登录您的mysql
mysql -u username
然后跑
FLUSH PRIVILEGES;
然后设置密码
SET PASSWORD FOR 'username'@'localhost' = PASSWORD('[password]');