Jefferson questions

Jefferson answers

• Heroku rake db:migrate error
• How to get most recent date value from array of hashes
• Rake db:seed rake aborted! ActiveRecord::RecordInvalid: Validation failed: Email has already been taken
• rails - apply default value for enum field
• Rails 4 devise: How to log out all users
• rake db:create vs rake db:create:all
• Error Parsing 'Gemfile'
• LoadError: cannot load such file — bcrypt_ext