ruby-on-rails - MySQL 问题 - RAILS_ENV=production bundle exec rake db :migrate

由于 detailed manual ，我只是将 redmine 安装到我的服务器上。一切都很好，但最后一步失败了一些错误，我不知道如何修复它。

命令是

RAILS_ENV=production bundle exec rake db:migrate

输出错误

You cannot specify the same gem twice with different version requirements.
You specified: mysql (>= 0) and mysql (~> 2.9.1)

gem 列表

*** LOCAL GEMS ***

actionmailer (3.2.15)
actionpack (3.2.15)
activemodel (3.2.15)
activerecord (3.2.15)
activeresource (3.2.15)
activesupport (3.2.15)
arel (3.0.3)
bigdecimal (1.2.0)
builder (3.0.0)
bundler (1.3.5)
capybara (2.1.0)
childprocess (0.3.9)
coderay (1.1.0)
daemon_controller (1.1.7)
database_cleaner (1.2.0)
erubis (2.7.0)
ffi (1.9.3)
hike (1.2.3)
hoe (3.7.1)
i18n (0.6.4)
io-console (0.4.2)
journey (1.0.4)
jquery-rails (2.0.3)
json (1.8.1, 1.7.7)
mail (2.5.4)
metaclass (0.0.1)
mime-types (1.25.1)
mini_portile (0.5.2)
minitest (4.3.2)
mocha (0.14.0)
multi_json (1.8.2)
mysql (2.9.1)
net-ldap (0.3.1)
nokogiri (1.6.0)
passenger (4.0.25)
polyglot (0.3.3)
psych (2.0.0)
rack (1.5.2, 1.4.5)
rack-cache (1.2)
rack-openid (1.4.1)
rack-ssl (1.3.3)
rack-test (0.6.2)
rails (3.2.15)
railties (3.2.15)
rake (0.9.6, 0.8.7)
rdoc (4.0.0, 3.12.2)
RedCloth (4.2.9)
rmagick (2.13.2)
ruby-openid (2.3.0)
rubygems-update (2.1.11)
rubytree (0.5.2)
rubyzip (1.0.0)
selenium-webdriver (2.37.0)
shoulda (3.3.2)
shoulda-context (1.0.2)
shoulda-matchers (1.4.1)
sprockets (2.2.2)
test-unit (2.0.0.0)
thor (0.18.1)
tilt (1.4.1)
treetop (1.4.15)
tzinfo (0.3.38)
websocket (1.0.7)
xpath (2.0.0)
yard (0.8.7.3)

Gemfile

    source 'https://rubygems.org'

    gem "rake", "0.8.7"
    gem "rack", "1.4.5"
    gem "i18n", "0.6.4"
    gem "rubytree", "0.5.2", :require => "tree"
    gem "RedCloth", "~>4.2.3", :require => "redcloth" # for CodeRay
    gem "mysql"

    gem "rails", "3.2.15"
    gem "jquery-rails", "~> 2.0.2"
    gem "coderay", "~> 1.1.0"
    gem "fastercsv", "~> 1.5.0", :platforms => [:mri_18, :mingw_18, :jruby]
    gem "builder", "3.0.0"

    # Optional gem for LDAP authentication
    group :ldap do
      gem "net-ldap", "~> 0.3.1"
    end

    # Optional gem for OpenID authentication
    group :openid do
      gem "ruby-openid", "~> 2.3.0", :require => "openid"
      gem "rack-openid"
    end

    # Optional gem for exporting the gantt to a PNG file, not supported with jruby
    platforms :mri, :mingw do
      group :rmagick do
        # RMagick 2 supports ruby 1.9
        # RMagick 1 would be fine for ruby 1.8 but Bundler does not support
        # different requirements for the same gem on different platforms
        gem "rmagick", ">= 2.0.0"
      end
    end

    platforms :jruby do
      # jruby-openssl is bundled with JRuby 1.7.0
      gem "jruby-openssl" if Object.const_defined?(:JRUBY_VERSION) && JRUBY_VERSION < '1.7.0'
      gem "activerecord-jdbc-adapter", "~> 1.3.2"
    end

    # Include database gems for the adapters found in the database
    # configuration file
    require 'erb'
    require 'yaml'
    database_file = File.join(File.dirname(__FILE__), "config/database.yml")
    if File.exist?(database_file)

   database_config = YAML::load(ERB.new(IO.read(database_file)).result)
   adapters = database_config.values.map {|c| c['adapter']}.compact.uniq
   if adapters.any?

    adapters.each do |adapter|
      case adapter
      when 'mysql2'
        gem "mysql2", "~> 0.3.11", :platforms => [:mri, :mingw]
        gem "activerecord-jdbcmysql-adapter", :platforms => :jruby
      when 'mysql'
        gem "mysql", "~>2.9.1", :platforms => [:mri, :mingw]
        gem "activerecord-jdbcmysql-adapter", :platforms => :jruby
      when /postgresql/
        gem "pg", ">= 0.11.0", :platforms => [:mri, :mingw]
        gem "activerecord-jdbcpostgresql-adapter", :platforms => :jruby
      when /sqlite3/
        gem "sqlite3", :platforms => [:mri, :mingw]
        gem "activerecord-jdbcsqlite3-adapter", :platforms => :jruby
      when /sqlserver/
        gem "tiny_tds", "~> 0.5.1", :platforms => [:mri, :mingw]
        gem "activerecord-sqlserver-adapter", :platforms => [:mri, :mingw]
      else
        warn("Unknown database adapter `#{adapter}` found in config/database.yml, use

    Gemfile.local to load your own database gems")
          end
        end
      else
        warn("No adapter found in config/database.yml, please configure it first")
      end
    else
      warn("Please configure your config/database.yml first")
    end

    group :development do
      gem "rdoc", ">= 2.4.2"
      gem "yard"
    end

    group :test do
      gem "shoulda", "~> 3.3.2"
      gem "mocha", ">= 0.14", :require => 'mocha/api'
      if RUBY_VERSION >= '1.9.3'
        gem "capybara", "~> 2.1.0"
        gem "selenium-webdriver"
        gem "database_cleaner"
      end
    end

    local_gemfile = File.join(File.dirname(__FILE__), "Gemfile.local")
    if File.exists?(local_gemfile)
      puts "Loading Gemfile.local ..." if $DEBUG # `ruby -d` or `bundle -v`
      instance_eval File.read(local_gemfile)
    end

    # Load plugins' Gemfiles
    Dir.glob File.expand_path("../plugins/*/Gemfile", __FILE__) do |file|
      puts "Loading #{file} ..." if $DEBUG # `ruby -d` or `bundle -v`
      #TODO: switch to "eval_gemfile file" when bundler >= 1.2.0 will be required (rails 4)
      instance_eval File.read(file), file
    end

谢谢你的任何回答。

美好的一天
简

最佳答案

当您在 mysql 中循环 adapters 时，您似乎包含了 Gemfile gem。从 Gemfile 中删除以下行后，您就可以开始使用了:

gem "rake", "0.8.7"
gem "rack", "1.4.5"
gem "i18n", "0.6.4"
gem "rubytree", "0.5.2", :require => "tree"
gem "RedCloth", "~>4.2.3", :require => "redcloth" # for CodeRay
gem "mysql" # <---------------- Remove this line.

关于ruby-on-rails - MySQL 问题 - RAILS_ENV=production bundle exec rake db :migrate，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/20242417/