Ruby On Rails MCQ Questions Answers

1. Which code sample will skip running the login_required "before" filter on the get_posts controller action?

2. Which choice is an incorrect way to render a partial?

3. Given a table of blog_posts and a related table of comments (comments made on each blog post), which ActiveRecord query will retrieve all blog posts with comments created during @range?

4. Which choice is not a valid Rails route?

5. If User is an ActiveRecord class, which choice would be expected to return an array?

6. Which part of the Rails framework is primarily responsible for making decisions about how to respond to a browser request?

7. Which choice best describes the expected value of @result? @result = Article.first.tags.build(name: 'Urgent')

8. Which statement about ActiveRecord models is true?

9. Review the code below. Which Ruby operator should be used to fill in the blank so that the sort method executes properly? [5,8,2,6,1,3].sort {|v1,v2| v1 ___ v2}

10. In a Rails controller, what does the code params.permit(:name, :sku) do?

11. Which Rails helper would you use in the application view to protect against CSRF (Cross-Site Request Forgery) attacks?

12. When Ruby methods add an exclamation point at the end of their name (such as sort!), what does it typically indicate?

13. What is a popular alternative template language for generating views in a Rails app that is focused on simple abstracted markup?

14. If a model class is named Product, in which database table will ActiveRecord store and retrieve model instances?

15. What is the correct way to generate a ProductsController with an index action using only the command-line tools bundled with Rails?

16. In Rails, what caching stores can be used?

17. If the Rails asset pipeline is being used to serve JavaScript files, how would you include a link to one of those JavaScript files in a view?

18. Where should you put images, JavaScript, and CSS so that they get processed by the asset pipeline?

19. How would you render a view using a different layout in an ERB HTML view?

20. How do you add Ruby code inside Rails views and have its result outputted in the HTML file?

21. In ActiveRecord, what is the difference between the has_many and has_many :through associations?

22. You are using an existing database that has a table named coffee_orders. What would the ActiveRecord model be named in order to use that table?

23. When using an ActiveRecord model, which method will create the model instance in memory and save it to the database?

24. What is the reason for using Concerns in Rails?

25. In Rails, how would you cache a partial template that is rendered?

26. Given the URL helper product_path(@product), which statement would be expected to be false?

27. For a Rails validator, how would you define an error message for the model attribute address with the message "This address is invalid"?

28. How would you generate a drop-down menu that allows the user to select from a collection of product names?

29. When a validation of a field in a Rails model fails, where are the messages for validation errors stored?

30. Are instance variables set within a controller method accessible within a view?

31. Which ActiveRecord query prevents SQL injection?

32. Which choice includes standard REST HTTP verbs?

33. In Rails, which code would you use to define a route that handles both the PUT and PATCH REST HTTP verbs?

34. Which module can you use to encapsulate a cohesive chunk of functionality into a mixin?

35. What is before_action (formerly known as before_filter)?

36. Which statement correctly describes a difference between the form helper methods form_tag and form_for?

37. Within a Rails controller, which code will prevent the parent controller's before_action :get_feature from running?

38. When rendering a partial in a view, how would you pass local variables for rendering?

39. What does the expression x ||= y mean?

40. Which gems is used for authentication in Ruby on Rails? (check any that apply)

41. What is the CGI Library? (check any that apply)

42. The send_data method has the following options? send_data(data, options = {})

43. Which will print correct date? format('Birthday: #{month}/#{day}/#{year}', day: 14, month: 11, year: 1994) format('Birthday: %d/%d/%d', 11, 14, 1994) format('Birthday: %{month}/%{day}/%{year}', day: 14, month: 11, year: 1994) format('Birthday: %{month}/%{day}/%{year}', 11, 14, 1994)

44. Which of these files are located by default in 'config' directory? (check any that apply)

45. Which of these filters do not exist in Rails controller? (check any that apply)

46. Which folder do not exist in folder “app” in Rails 5? (check any that apply)

47. Which URL's will not be created by method resources :posts in routes.rb?

48. Which of these statements about Ruby on Rails 5 are false?

49. Why would let() be used in rspec?

50. What is the SQL equivalent of following code? user=User.take(3)

51. Which code snippet can be used to include all javascript files?

52. Which code snippet can be used to include all javascript files?

53. Which command will you use in Updates Ruby in the latest version?

54. While installing Ruby, why do you sometimes get a missing 'psych' error?

55. Which code is correct about Creating links

56. What is the top-level model class added in Ruby on Rails 5?

57. Which type of field is recommended for storing 'enum' in Rails?

58. Which of these server is the default development server for Ruby on Rails 5?

59. Which of these model methods will be generated by this code? enum state: { blocked: 0, active: 1 }

60. Which of these methods catch Exception in Rails controllers?

61. Which of these routes is not generated by “resource :user”?

62. Which will open directly is correct about Open URI?

63. Which code will raise an exception? class Person def name 'Andrew' end end # 1. person = Person.new person .name # 2. person = Person.new person. name # 3. Person .new .name # 4. Person .name

64. Which is the correct way to add a field in a signup that is not present in the User Model?

65. Which of these expressions is equivalent to this code? a ||= 'string'

66. Which represents the inverse of a has_one association?

67. In order to use optimistic locking, the table needs to have a column called ___________ of type integer.

68.

69. Which notation is used to create class variables?

70. render method does not accept ________________

71. Which method is used to render partial templates as part of a view?

72. Which type of association is not supported by ActiveRecord?

73. Which helper should be used when your model has association with other models and they also need to be validated?

74. State whether True or False The find method will raise an ActiveRecord::RecordNotFound exception unless a matching record is found for all the supplied primary keys.

75. What is the difference between find() and find_by_id() method?

76. How to disable protection of CSRF attacks for API requests?

77. Which method is used in views to prevent CSRF attack?

78. Which methods can be used inside a controller to prevent CSRF attack?

79. What is the difference between Lambdas and procs?

80. Which file contains the database credentials of an RoR application?

81. Which rake commands can be used to load a schema.rb file into the database?

82. Which file contains the Gem requirements of an RoR App?

83. Which command is used to list all the routes of an RoR application?

84. Which is used to achieve multiple inheritance in Ruby?

85. Which declaration can be used to override the default layout conventions in your controllers?

86. Which of the following loops is not supported by Ruby?

87. The belongs_to association supports following options? A) :autosavename, :class_id B) :primary_key, :validate, :optional C) :conuter_cache, :inverse_of, :foreign_key D) :dependent, :polymorphic, :touch

88. The has_one association supports following options?

89. Which of these options for 'dependent' do not exist in Rails?

90. How is it possible to create combined unique index for two fields?

91. How do you permit nester attributes in Rails controllers for such model? class User has_one :profile accepts_nested_attributes_for :profile end

92. Which of the following statements are correct about Types of Templates? (choose all that apply)

93. The following methods skip validations, and will save the object to the database regardless of its validity?

94. Difference between 'has_many :through' and 'has_and_belongs_to_many'?

95. Purpose of using below code in filter_parameter_logging.rb? Rails.application.config.filter_parameters += [:password]

96. A controller is a server-side _____ of Rails that responds to external requests from the web server to the application?

97. In Ruby on Rails, an action is typically a basic ____ that describes how to respond to a specific external web-browser request?

98. Which instances are variables in your functional tests? (check any that apply)

99. What are the Available callbacks? (check any that apply)

100. Which of these is not a valid Bundler command?