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* Upwork Ruby on Rails Test Answer N0 1.

Question:

Unit tests are used to test which of the following components of Ruby on Rails?

Answers:

Models

* Upwork Ruby on Rails Test Answer N0 2.

Question:

Which of the following commands will test a particular test case, given that the tests are contained in the file test/unit/demo_test.rb, and the particular test case is test_one?

Answers:

$ ruby -Itest test/unit/demo_test.rb -n test_one

* Upwork Ruby on Rails Test Answer N0 3.

Question:

Rails automatically requires certain files in an application. Which of the following files are automatically included without an explicit 'require' being necessary?

Answers:

All files in models, views, controllers, and any init.rb in plugins.

* Upwork Ruby on Rails Test Answer N0 4.

Question:

Select all incorrect statements regarding the Ruby Version Manager (RVM):

Answers:

RVM provides a revision control tool to maintain current and historical versions of files such as source code, web pages, and documentation.

* Upwork Ruby on Rails Test Answer N0 5.

Question:

Answers:

nil, 0, and any positive integer

* Upwork Ruby on Rails Test Answer N0 6.

Question:

What is the behavior of class variables with subclasses?

Answers:

Class variables are shared between between all classes in the hierarchy.

* Upwork Ruby on Rails Test Answer N0 7.

Question:

In a has_many association, what is the difference between build and new? // user.rb has_many :posts // post.rb belongs_to :user

Answers:

'build' sets the foreign key and adds it to the collection.

* Upwork Ruby on Rails Test Answer N0 8.

Question:

If a method #decoupage(n) is described as O(n^2), what does that mean?

Answers:

The worst case run time is proportional to the size of the square of the method's input.

* Upwork Ruby on Rails Test Answer N0 9.

Question:

Which of the following controller actions (by default) are best suited to handle the GET HTTP request?

Answers:

index

* Upwork Ruby on Rails Test Answer N0 10.

Question:

In a Rails application, a Gemfile needs to be modified to make use of sqlite3-ruby gems. Which of the following options will use these gems, as per the new Gemfile?

Answers:

bundle install

* Upwork Ruby on Rails Test Answer N0 11.

Question:

What component of Rails are tested with unit tests?

Answers:

Models

* Upwork Ruby on Rails Test Answer N0 12.

Question:

How can a partial called "cart" be rendered from a controller called "ProductsController", assuming the partial is in a directory called "shared"?

Answers:

render :partial => 'shared/cart'

* Upwork Ruby on Rails Test Answer N0 13.

Question:

Which of the following options is used to create a form HTML in the erb files?

Answers:

form_for

* Upwork Ruby on Rails Test Answer N0 14.

Question:

Given below are two statements regarding the Ruby programming language: Statement X: "redo" restarts an iteration of the most internal loop, without checking loop condition. Statement Y: "retry" restarts the invocation of an iterator call. Also, arguments to the iterator are re-evaluated. Which of the following options is correct?

Answers:

Both statements are correct.

* Upwork Ruby on Rails Test Answer N0 15.

Question:

Which of the following options, when passed as arguments, skips a particular validation?

Answers:

:validate => false

* Upwork Ruby on Rails Test Answer N0 16.

Question:

Which of the following is not a built-in Rails caching strategy used to reduce database calls?

Answers:

Query Caching

* Upwork Ruby on Rails Test Answer N0 17.

Question:

How can a value be stored so that it's shared across an entire request (i.e. make it accessible in controllers, views and models)?

Answers:

Create a Singleton and store it in a class variable

* Upwork Ruby on Rails Test Answer N0 18.

Question:

Which is the best way to add a page-specific JavaScript code in a Rails 3 app? <%= f.radio_button :rating, 'positive', :onclick => "$('some_div').show();" %>

Answers:

<% content_for :head do %> <script type="text/javascript"> <%= render :partial => "my_view_javascript" </script> <% end %> Then in layout file <head> ... <%= yield :head %> </head>

* Upwork Ruby on Rails Test Answer N0 19.

Question:

Which part of the MVC stack does ERB or HAML typically participate in?

Answers:

View

* Upwork Ruby on Rails Test Answer N0 20.

Question:

Which of the following choices will write routes for the API versioning scenario described below? /api/users returns a 301 to /api/v2/users /api/v1/users returns a 200 of users index at version 1 /api/v3/users returns a 301 to /api/v2/users /api/asdf/users returns a 301 to /api/v2/users

Answers:

• namespace :api do namespace :v1 do resources :users end namespace :v2 do resources :users end match 'v:api/*path', :to => redirect("/api/v2/%{path}") match '*path', :to => redirect("/api/v2/%{path}") end • namespace :api do resources :users end namespace :v2 do resources :users end match 'v:api/*path', :to => redirect("/api/v1/%{path}") match '*path', :to => redirect("/api/v1/%{path}") end • namespace :api do scope :module => :v3, ¤t_api_routes namespace :v3, ¤t_api_routes namespace :v2, ¤t_api_routes namespace :v1, ¤t_api_routes match ":api/*path", :to => redirect("/api/v3/%{path}") end • None of these

* Upwork Ruby on Rails Test Answer N0 21.

Question:

Which of the following replaced the Prototype JavaScript library in Ruby on Rails as the default JavaScript library?

Answers:

jQuery

* Upwork Ruby on Rails Test Answer N0 22.

Question:

What is the difference between _url and _path while being used in routes?

Answers:

_url is absolute while _path is relative.

* Upwork Ruby on Rails Test Answer N0 23.

Question:

Answers:

a href='Angel'>/users/1</a

* Upwork Ruby on Rails Test Answer N0 24.

Question:

Users who are new to MVC design often ask how to query data from Views. Is this possible? And if so, is this a good idea?

Answers:

It is possible, but it is a bad idea because Views should only be responsible for displaying objects passed to them

* Upwork Ruby on Rails Test Answer N0 25.

Question:

When using full-page caching, what happens when an incoming request matches a page in the cache?

Answers:

The web-server serves the file directly from disk, bypassing Rails

* Upwork Ruby on Rails Test Answer N0 26.

Question:

What is the best way to get the current request URL in Rails?

Answers:

request.url

* Upwork Ruby on Rails Test Answer N0 27.

Question:

Which of the following commands will clear out sample users from the development database?

Answers:

rake db:reset

* Upwork Ruby on Rails Test Answer N0 28.

Question:

Which of the following options will disable the rendering of the view associated with a controller action?

Answers:

render :layout=>false

* Upwork Ruby on Rails Test Answer N0 29.

Question:

What is the Singleton design pattern?

Answers:

A class for which there is only ever one instance.

* Upwork Ruby on Rails Test Answer N0 30.

Question:

Which of the following code samples will get the index of |page| inside of a loop?

Answers:

<% @images.each_with_index do |page, index| %> <% end %>

* Upwork Ruby on Rails Test Answer N0 31.

Question:

Which of the following is not true about log levels in Ruby on Rails?

Answers:

The available log levels are: :debug, :info, :warn, :error, and :fatal, corresponding to the log level numbers from 1 up to 5 respectively.

* Upwork Ruby on Rails Test Answer N0 32.

Question:

Which of the following validations in Rails checks for null fields?

Answers:

validates_presence_of

* Upwork Ruby on Rails Test Answer N0 33.

Question:

In order to enable locking on a table, which of the following columns is added?

Answers:

lock_version column

* Upwork Ruby on Rails Test Answer N0 34.

Question:

Answers:

1) false 2) true 3) NoMethodError: undefined method `empty?' for nil:NilClass 4) true 5) NoMethodError: undefined method `any?' for "":String 6) false

* Upwork Ruby on Rails Test Answer N0 35.

Question:

Which of the following will return a User object when used with a model which deals with a table named User?

Answers:

User.find

* Upwork Ruby on Rails Test Answer N0 36.

Question:

Which of the following is the correct way to know the Rails root directory path?

Answers:

Rails.root

* Upwork Ruby on Rails Test Answer N0 37.

Question:

For the String class, what's the difference between "#slice" and "#slice!"?

Answers:

"#slice" returns a new object, "#slice!" destructively updates — mutates — the object's value.

* Upwork Ruby on Rails Test Answer N0 38.

Question:

Which of the following is the correct way to rollback a migration?

Answers:

rake db:rollback STEP=N (N is the migration number to be rollbacked)

* Upwork Ruby on Rails Test Answer N0 39.

Question:

What is the output of the following code? "test"*5

Answers:

testtesttesttesttest

* Upwork Ruby on Rails Test Answer N0 40.

Question:

If a controller is named "Users", what would its helpers module be called?

Answers:

UsersHelper

* Upwork Ruby on Rails Test Answer N0 41.

Question:

Which of the following is the correct syntax for an input field of radio buttons in form_for?

Answers:

<%= f.radio_button :contactmethod, 'sms' %>

* Upwork Ruby on Rails Test Answer N0 42.

Question:

Answers:

A

* Upwork Ruby on Rails Test Answer N0 43.

Question:

In the case of Rails application performance optimization, select all valid ways to do assets compilation:

Answers:

Running the rake task with the assets:precompile parameter when CSS and JavaScript files are updated.

* Upwork Ruby on Rails Test Answer N0 44.

Question:

Which of the following actions is fired by default when a new controller is created?

Answers:

Index

* Upwork Ruby on Rails Test Answer N0 45.

Question:

What does REST stand for?

Answers:

REpresentational State Transfer

* Upwork Ruby on Rails Test Answer N0 46.

Question:

What is green-threading?

Answers:

When threads are emulated by a virtual machine or interpreter.

* Upwork Ruby on Rails Test Answer N0 47.

Question:

What is the convention for methods which end with a question mark? e.g. #all?, #kind_of?, directory?

Answers:

They should always return a boolean value.

* Upwork Ruby on Rails Test Answer N0 48.

Question:

What is the output of the following code? $val = 20 print "Sample Text\n" if $val

Answers:

Sample Text

* Upwork Ruby on Rails Test Answer N0 49.

Question:

Choose the best way to implement sessions in Rails 3: A) Using CookieStore B) By creating a session table and setting config/initializers/session_store.rb with Rails.application.config.session_store :active_record_store C) By setting config/initializers/session_store.rb with Rails.application.config.session_store :active_record_store only

Answers:

B

* Upwork Ruby on Rails Test Answer N0 50.

Question:

Which of the following is the default way that Rails seeds data for tests?

Answers:

Fixtures

* Upwork Ruby on Rails Test Answer N0 51.

Question:

When a new controller named "admin2" is created, the JS and the CSS files are created in:

Answers:

assets

* Upwork Ruby on Rails Test Answer N0 52.

Question:

If a float is added to an integer, what is the class of the resulting number? i.e. 1.0 + 2

Answers:

FLOAT

* Upwork Ruby on Rails Test Answer N0 53.

Question:

Which of the following methods is used to check whether an object is valid or invalid?

Answers:

.valid? and .invalid?

* Upwork Ruby on Rails Test Answer N0 54.

Question:

Which of the following serves as a structural skeleton for all HTML pages created?

Answers:

application.html.erb

* Upwork Ruby on Rails Test Answer N0 55.

Question:

Suppose a model is created as follows: rails generate model Sales rake db:migrate What would be the best way to completely undo these changes, assuming nothing else has changed in the meantime?

Answers:

rake db:rollback; rails destroy model Sales

* Upwork Ruby on Rails Test Answer N0 56.

Question:

Which of the following is the correct way to skip ActiveRecords in Rails 3?

Answers:

Which of the following is the correct way to skip ActiveRecords in Rails 3?

* Upwork Ruby on Rails Test Answer N0 57.

Question:

Which of the following assertions are used in testing views?

Answers:

assert_select_encoded

* Upwork Ruby on Rails Test Answer N0 58.

Question:

Given the following code, where is the "party!" method available? module PartyAnimal def self.party! puts "Hard! Better! Faster! Stronger!" end end class Person include PartyAnimal end

Answers:

PartyAnimal.party!

* Upwork Ruby on Rails Test Answer N0 59.

Question:

What does the 4xx series of HTTP errors represent?

Answers:

They are intended for cases in which the server seems to have encountered an error.

* Upwork Ruby on Rails Test Answer N0 60.

Question:

What exception cannot be handled with the rescue_from method in the application controller? e.g class ApplicationControllers < ActionController::Base rescue_from Exception, with: error_handler .......... end

Answers:

Server errors

* Upwork Ruby on Rails Test Answer N0 61.

Question:

Which of the following will disable browser page caching in Rails?

Answers:

expire_page(:controller => 'products', :action => 'index')

* Upwork Ruby on Rails Test Answer N0 62.

Question:

Answers:

The HTML page will render with the title: Ruby on Rails sample application |.

* Upwork Ruby on Rails Test Answer N0 63.

Question:

In a Rails application, the developmental and production configuration are stored in the:

Answers:

config/environment folder

* Upwork Ruby on Rails Test Answer N0 64.

Question:

Which of the following is true about writing tests for a Ruby on Rails application?

Answers:

• Rails semi-automates the process of writing tests. It starts by producing skeleton test code in the background while models and controllers are being written. • Running tests in Rails ensures that the code adheres to the desired functionality even after major code refactoring. • Rails tests can simulate browser requests, and thus test the application's response without having to test it through a browser. • All of these.

* Upwork Ruby on Rails Test Answer N0 65.

Question:

With the two models Hive and Bee; when creating a belongs_to association from the Bee model to Hive, what is the foreign key generated on Bee?

Answers:

hive_id

* Upwork Ruby on Rails Test Answer N0 66.

Question:

What is the recommended Rails way to iterate over records for display in a view?

Answers:

Implicitly loop over a set of records, and send the partial being rendered a :collection.

* Upwork Ruby on Rails Test Answer N0 67.

Question:

What is difference between "has_one" and "belong_to"?

Answers:

"belong_to" should be used in a model whose table have foreign keys while "has_one" is used with an associated table.

* Upwork Ruby on Rails Test Answer N0 68.

Question:

where we use attr_accessor and attr_accessible in rails ?

Answers:

model

* Upwork Ruby on Rails Test Answer N0 69.

Question:

What is the output of the following code? puts "aeiou".sub(/[aeiou]/, '*')

Answers:

*eiou

* Upwork Ruby on Rails Test Answer N0 70.

Question:

What declaration would you use to set the layout for a controller?

Answers:

layout 'new_layout'

* Upwork Ruby on Rails Test Answer N0 71.

Question:

Which of the following statements is incorrect?

Answers:

Rails does not support ODBC connectivity.

* Upwork Ruby on Rails Test Answer N0 72.

Question:

What is the output of the following Ruby code? puts "The multiplication output of 10,10,2 is #{10*10*2}"

Answers:

The multiplication output of 10,10,2 is 200.

* Upwork Ruby on Rails Test Answer N0 73.

Question:

What is best way to create primary key as a string field instead of integer in rails.

Answers:

when creating a new table don't add primary key using this create_table users, :id => false do |t| t.string :id, :null => false ...... end execute("ALTER TABLE users ADD PRIMARY KEY (id)") if not using id as primary key then in users model add the following line class User < ActiveRecord::Base self.primary_key = "column_name" .... end

* Upwork Ruby on Rails Test Answer N0 74.

Question:

There is a table named Product in a Rails application. The program is required to fetch any 5 rows where the productid is 2. Which of the following is the correct option to perform this action?

Answers:

Product.find(:productid=>2), :limit=>5

* Upwork Ruby on Rails Test Answer N0 75.

Question:

Which of the following commands adds the data model info to the model file?

Answers:

generate model

* Upwork Ruby on Rails Test Answer N0 76.

Question:

Which gem is used to install a debugger in Rails 3?

Answers:

gem "ruby-debug19"

* Upwork Ruby on Rails Test Answer N0 77.

Question:

Is an AJAX call synchronous or asynchronous?

Answers:

Either; it is configurable

* Upwork Ruby on Rails Test Answer N0 78.

Question:

If a model called BlogComment is defined, what would its DB table be called?

Answers:

blog_comments

* Upwork Ruby on Rails Test Answer N0 79.

Question:

Which of the following items are stored in the models subdirectory?

Answers:

database classes

* Upwork Ruby on Rails Test Answer N0 80.

Question:

What is the output of the following code in Ruby? x= "A" + "B" puts x y= "C" << "D" puts y

Answers:

AB CD

* Upwork Ruby on Rails Test Answer N0 81.

Question:

In a Rails Migration, which of the following will make a column unique, and then have it indexed?

Answers:

add_index :table_name, :column_name, :unique => true

* Upwork Ruby on Rails Test Answer N0 82.

Question:

How can a partial called "cart" be rendered from a controller called "ProductsController", assuming the partial is in a directory called "shared"?

Answers:

render :partial => 'shared/cart'

* Upwork Ruby on Rails Test Answer N0 83.

Question:

What is the difference between :dependent => :destroy and :dependent => :delete_all in Rails?

Answers:

In :destroy, associated objects are destroyed alongside the object by calling their :destroy method, while in :delete_all, they are destroyed immediately, without calling their :destroy method.

* Upwork Ruby on Rails Test Answer N0 84.

Question:

Using ERB for views, what filename should be given to a partial called 'login'?

Answers:

_login.html.e

* Upwork Ruby on Rails Test Answer N0 85.

Question:

Which of the following HTML template languages are supported by Ruby?

Answers:

Embedded Ruby