小编Mat*_*vic的帖子

所以我试图将一个小项目部署到Heroku,但是当我部署它并尝试运行heroku run rake db:migrate它时返回给我以下错误:

rake aborted!
Gem::LoadError: 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).
/app/vendor/bundle/ruby/2.2.0/gems/activerecord-4.2.6/lib/active_record/connection_adapters/connection_specification.rb:177:in `rescue in spec'
/app/vendor/bundle/ruby/2.2.0/gems/activerecord-4.2.6/lib/active_record/connection_adapters/connection_specification.rb:174:in `spec'
/app/vendor/bundle/ruby/2.2.0/gems/activerecord-4.2.6/lib/active_record/connection_handling.rb:50:in `establish_connection'
/app/vendor/bundle/ruby/2.2.0/gems/activerecord-4.2.6/lib/active_record/railtie.rb:120:in `block (2 levels) in <class:Railtie>'
/app/vendor/bundle/ruby/2.2.0/gems/activesupport-4.2.6/lib/active_support/lazy_load_hooks.rb:38:in `instance_eval'
/app/vendor/bundle/ruby/2.2.0/gems/activesupport-4.2.6/lib/active_support/lazy_load_hooks.rb:38:in `execute_hook'
/app/vendor/bundle/ruby/2.2.0/gems/activesupport-4.2.6/lib/active_support/lazy_load_hooks.rb:28:in `block in on_load'
/app/vendor/bundle/ruby/2.2.0/gems/activesupport-4.2.6/lib/active_support/lazy_load_hooks.rb:27:in `each'
/app/vendor/bundle/ruby/2.2.0/gems/activesupport-4.2.6/lib/active_support/lazy_load_hooks.rb:27:in `on_load'
/app/vendor/bundle/ruby/2.2.0/gems/activerecord-4.2.6/lib/active_record/railtie.rb:116:in `block in <class:Railtie>'
/app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.6/lib/rails/initializable.rb:30:in `instance_exec'
/app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.6/lib/rails/initializable.rb:30:in `run'
/app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.6/lib/rails/initializable.rb:55:in `block in run_initializers'
/app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.6/lib/rails/initializable.rb:54:in `run_initializers'
/app/vendor/bundle/ruby/2.2.0/gems/railties-4.2.6/lib/rails/application.rb:352:in `initialize!'
/app/config/environment.rb:5:in …

我正在尝试使用Flask网站上的SteamID片段登录.但是,ImportError: No module named flaskext.sqlalchemy当我尝试运行它时,我得到了,并且PyCharm说Uresolved reference "flaskext"和Uresolved reference "OpenID".我重新安装了Flask-OpenID和Flask-SQLAlchemy,以确保它们在那里.为什么我会收到此错误,如何解决？