Ruby Gemfile无法添加PostgreSQL gem

Question

这是我的Gemfile：

source 'https://rubygems.org'

#my added gems
gem 'pg', '~> 0.17.1'
gem 'rails_12factor', '0.0.2'

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '4.1.0'
# Use sqlite3 as the database for Active Record
gem 'sqlite3'
# Use SCSS for stylesheets
gem 'sass-rails', '~> 4.0.3'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# Use CoffeeScript for .js.coffee assets and views
gem 'coffee-rails', '~> 4.0.0'
# See https://github.com/sstephenson/execjs#readme for more supported runtimes
# gem 'therubyracer',  platforms: :ruby

# Use jquery as the JavaScript library
gem 'jquery-rails'
# Turbolinks makes following links in your web application faster. Read more: https://github.com/rails/turbolinks
gem 'turbolinks'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.0'
# bundle exec rake doc:rails generates the API under doc/api.
gem 'sdoc', '~> 0.4.0',          group: :doc

# Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
gem 'spring',        group: :development

您可以在第四行看到为pg gem添加的行。 在终端中保存并运行bundle install ，出现以下错误，并显示以下错误：

An error occurred while installing pg (0.17.1), and Bundler cannot continue.
Make sure that `gem install pg -v '0.17.1'` succeeds before bundling.

有人知道如何解决这个问题吗？

Answer 1

捆绑安装之前，您是否尝试过该提示信息？

 gem install pg -v '0.17.1'

另外，如果您在本地运行此程序，并且需要postrgre只是将应用程序部署到类似Heroku的服务器（您在本地使用sqlite / mysql），则将其添加到生产环境中，如下所示：

 group :production do
   gem 'pg'
 end

并运行

   bundle install 

再次。