Ruby On Rails Questions

Question

Rails:

Basic:

1. What's new in rails 4?
2. Difference b/w rails 3 and rails 4?
3. Difference b/w rails 2 and rails 4?
4. Where will you write the reusable code for controller in rails 4 ? (concerns)
5. Where will you write the reusable code for model in rails 4 ? (concerns)
6. What are gems in rails?
7. What is difference b/w gems and plugins?
8. What is difference b/w symbol and string?
9. What is caching? What is russian doll caching?
10. Why don't we use page caching and action caching. Also drawbacks for the same?
11.  What is difference b/w string and symbol?
12. Multiple inheritance in rails? And how can we use multiple inheritance in rails?
13. Method Overloading in rails?
14. Difference b/w include, extend and require?
15. STI and Polymorphic associations?
16. Different Examples for polymorphic association?
17. About yield?
18. Difference b/w class variables and instance variables?
19. How will you get and set the values without using attr_accessible?
20. How will you store foreign key to another column name?
21. What is difference between include and join?
22. Difference b/w proc and lambda?
23. Practical use of proc and lambda?
24. What is DRY principal?
25. What are RESTful routes?
26.  How many actions generated by scaffold command in rails 4?
27. What in difference b/w put and patch?
28. What is difference b/w get, put and post?
29. How can you define constructor in rails?
30. What is use of map in rails?
31. Best tool for security measurement in rails?
32. How everything in object in rails?
33. What are dynamic finders?
34. What is difference between session and cookies?
35. Dynamic Methods in rails?
36. What is use of bang (!) operator in rails?
37. What is use of module?
38. Is rails interpreted or compiled language?
39. Which files load first environment.rb and application.rb ? Difference?
40. Access modifier  in rails?
41. Use of scope?
42. What are sweepers and observers? Difference?
43. Actions and method difference?
44. What are filters?
45. How render works? render is slow so how can we fast our rendering?
46. What does request.xhr do?
47. What is use js.erb file?
48. Difference b/w render and redirect?
49. How can we call third party service using ajax?
50. What is Eager loading and lazy loading?
51. What are validations? Give example?
52.  What is use of helper method?
53. Sql Injection and cross site forgery request?
54. What is difference b/w render and redirect?
55. What are different type of joins?
56. What are turbolinks?
57. String and symbol which is better to use? (string GC)
58. What is garbage collector?
59. What are callbacks? Types?
60. How around_filter works?
61. Create DB design for project timesheets?
62. Use and How index works?
63. Preference of columns for indexing?
64. How capistrano works?
65. if everything is an object in rails so how class keyword in an object?
66.  Steps to increase page load speed?
67. If we write redirect_to google.com in action ? will it come back to site? What will happen?
68. Which loads first: layout's html file application.html.erb or action's html file like index.html.erb?
69. If action is not available into the controller and html occurs for the action so will rails show error or not?
70. How file loads? or hierarchy for loading the controller files?(alphabetically loads file)
71. Use of config.ru?
72. How routes call to particular action? An idea about routing?
73. What are cron Jobs?
74.  How to connect multiple databases?
75. Can a model file connect to some other database in rails? How?
76. Middleware in rails?
77. What are alias in rails?
78. How to create runtime methods?
79. How to create singleton class? an example in rails? (logs)
80. What are mixins?
81. What are virtual attributes?
82. What are whitelist/strong parameters?
83. Why we use strong parameters in rails 4? Reason behind that?
84. What is use of super?
85. Why we use self? 
86. Why not we use multiple inheritance and method overloading in rails?
87. How many type of exceptions are in rails?
88. How to enable you logging on production mode?
89. Custom validations?
90. Open classes?
91. What are the use of initializers?
92. Is internationalization occurs in rails?
93. What is rake?
94. Best practice to define constants?
95. What are named scope in routing?
96. What is use of concern in routing?
97. What is use of transaction method in rails?
98. What type of threading used in rails 4?
99. Which javascript library use by default in rails 4?
100. What is use of assets in rails ? 

OOPS :

Ques1: What is a class and object?
Ques2: How will you define a class (Real Time example) ?
Ques3: Why we need to create a class and why objects are created for a class ?
Ques4: What is use of class ?
Ques5: What is polymorphism, inheritance etc. Some basic oops concepts ?