Ruby On Rails MCQ Questions Answers

1. What command do you run to undo the last 5 migrations

2. A global variable has a name beginning with:

3. What gets returned by: [1, [2, 3,[4, 5]]].flatten

4. How can you create a new Rails project?

5. Which will delete the key-value 1 from array: 'big_data'?

6. What is the use of $ in Ruby?

7. What is the use of @@ in Ruby?

8. Which is NOT a default Rails environment?

9. What is a Gem?

10. Which extension is default for views html templates?

11. In the MVC pattern:

12. What is the command to install Rails?

13. What command do you run to create your database?

14. What command do you run to drop your database?

15. How would you declare an Instance Variable?

16. Ruby uses:

17. What command do you run to update your database?

18. Migrations...

19. What is the preferred method of validating that the name has been set?

20. Which will interpolate within a string with the variable named 'monster'?

21. What is the output of the following ? s='foo' * 2 puts s

22. What ORM does Ruby on Rails use by default?

23. What is a typical file extension found in the app/controllers directory

24. Which of these is not a standard directory in a Rails application?

25. The recommended directory in which to place your app's javascript files is:

26. Which files is used to specify any default data that should be loaded into the application's database, when it is first setup?

27. What is the default value for a global variable (before initialization)?

28. is it possible to change the default port when running a rails server ?

29. Which prints the 'Hello WORLD!' output with a new line?

30. How do you create a new user object with the name david and save it to the database?

31. Which of these does NOT correctly return the version of Ruby?

32. If you want the /person url to map to your dog controller and show method, what do you add to your routes?

33. What is the use of the 'defined?' method?

34. Which of these javascript frameworks became the default with the release of Rails 3.1?

35. What is the use of @ in Ruby?

36. Imagine that you have two models: 'User' and 'Book', and a user can have only one book. How should the association look like in the 'User' model?

37. What file will rails look for given the following erb: <%= render 'some_partial' %>?

38. Determine the value of the variable x after the execution of the following code. x = [1,2,3] x.pop until x.empty? x.push(4) while x.empty?

39. If you want to append an item to an array, what is the standard method?

40. which one is class method?

41. Which is NOT a model validation method?

42. What part of a migration runs during a rollback?

43. Which of the following is a working ruby while-loop?

44. A module cannot be subclassed or instantiated.

45. Where will routes.rb file appear?

46. If you want the standard restful routes for your person controller, how do you add that?

47. What is the difference between Symbol and String?

48. belongs_to: Represents the inverse of a has_one (or has_many) association.

49. Most elegant way to include a javascript file needed for only one page?

50. Which is NOT a Ruby operator?

51. Which command, when run, will compile all assets in the 'app/assets' directory and copy compiled versions to a configured target directory ('public/assets' by default)?

52. How do you remove a column during a migration?

53. If you create PostsController, where will Rails look for its templates by default?

54. Which will check the array named 'big_data' for the presence of a key 'icecream'?

55. Which is NOT an ActiveRecord query method?

56. If you have posts and each post has_many comments, how do you structure your routes?

57. Which of these is NOT a default subdirectory of the app/ directory?

58. How would you check to see if an array named COLORS contains the the value 'red'?

59. Which would create a new project without unit test?

60. Which is NOT a reserved Ruby logic flow word?

61. What is the output for the following? x = 1==1 ? 'a' : 'b'; puts x

62. What is not a RESTful controller action?

63. Where do you add named scopes?

64. Unit tests are used to test what part of a Rails application?

65. Which is an incorrectly defined method?

66. Which command would generate a DogController with a 'bark' action?

67. What is the main step to add ajax call in Ruby on Rails?

68. If you want to display the price of an item, with a :time_span tag, where would you place this code?

69. Which does NOT append 'nine' to the array: 'big_data'?

70. In the context of unit testing Rails applications, 'fixture' refers to which of the following?

71. What is the output of the following? @@x = 10 puts defined? @@x

72. Which of these is not a valid form helper?

73. Ruby 1.9, what new method of building key-value pairs is supported?

74. In a Rails migration, what's the syntax for creating a table?

75. When rendering a partial on a collection, what is the recommended method?

76. A correct example of class inheritance from 'Exception' into 'Bomber'

77. Which is NOT an ActiveRecord migration method?

78. Ruby supports single inheritance, multiple inheritance, or both?

79. A class variable (not class level instance variable) has a name beginning with ___________.

80. String objects are _______.

81. Does RoR supports multiple inheritance?

82. The session is, by default, accessible to:

83. Which of the following is a correctly formatted multi-line comment?

84. Functional tests are used to test what part of a Rails application?

85. What is the main function of helpers used in Ruby on Rails?

86. Which controller methods is NOT properly paired with its HTTP counterpart?

87. What is the output of the following? puts 'a\nb'

88. To randomize the order of entries in an Array, use the _______ method.

89. Which of these is NOT a valid way of associating models?

90. When you've got a form, and when the user submits invalid data, you redirect back to the edit form. If you want to show a general error message (not tied to validation errors) to the user, you'd do which of the following?

91. What is the output of the following? $x = 10 puts defined? $X

92. Which of these code blocks cannot be right?

93. Which column type is NOT supported by Active Record?

94. Which expression will not return a sum of array elements in Ruby on Rails?

95. What is the proper way to subclass a Module?

96. What is not a proper REST verb?

97. How does the Asset Pipeline (Rails 3.1 +) deal with different precompiled versions of an asset?

98. How do you render a variable in ERB template?

99. What kind of variables are Author and AUTHOR?

100. What does Model.reset_column_information do?