Ruby On Rails Interview Questions and Answers in 2025 (100+ Q&A)

Ruby On Rails

Ques:- What is the difference between render and redirect?

Asked In :-

Right Answer:
`render` displays a view template without changing the URL, while `redirect` sends a new request to a different URL, changing the URL in the browser.

Ruby On Rails

Ques:- What does session and cookies represent in ruby on rails?

Asked In :- Ulearn,

Right Answer:
In Ruby on Rails, sessions are used to store user-specific data on the server side, allowing data to persist across requests for a particular user. Cookies, on the other hand, are small pieces of data stored on the client side (in the user's browser) that can hold information to be sent back to the server with each request. Sessions are typically more secure for sensitive data, while cookies can be used for less sensitive information and can persist beyond the session.

Ruby On Rails

Ques:- What is the directory structure of rails?

Asked In :-

Right Answer:
The directory structure of a Ruby on Rails application typically includes the following main directories:

- `app/`: Contains the main application code (models, views, controllers, helpers, mailers, assets).
- `bin/`: Contains executable files for the application.
- `config/`: Contains configuration files for the application (routes, database, environment settings).
- `db/`: Contains database-related files (migrations, seeds).
- `lib/`: Contains custom libraries and modules.
- `log/`: Contains application log files.
- `public/`: Contains static files and the main entry point (index.html).
- `test/` or `spec/`: Contains test files (unit tests, integration tests).
- `vendor/`: Contains third-party code and libraries.

Each of these directories serves a specific purpose in organizing the application.

Ruby On Rails

Ques:- What are the different types of association relationships that exist?

Asked In :-

Right Answer:
In Ruby on Rails, the different types of association relationships are:

1. **belongs_to**: A one-to-one connection where a model references another model.
2. **has_one**: A one-to-one connection where a model has one instance of another model.
3. **has_many**: A one-to-many connection where a model can have multiple instances of another model.
4. **has_many :through**: A many-to-many connection through a join model.
5. **has_and_belongs_to_many**: A direct many-to-many connection without a join model.

Ruby On Rails

Ques:- What is the purpose of require_relative in ruby?

Asked In :-

Right Answer:
`require_relative` in Ruby is used to load a file relative to the file containing the `require_relative` statement, allowing for easier management of file dependencies within a project.

Ruby On Rails

Ques:- How to use two databases into a single application?

Asked In :- CodeStore,

Right Answer:
To use two databases in a single Ruby on Rails application, you can configure multiple database connections in your `database.yml` file and then use Active Record's `establish_connection` method in your models. For example:

1. In `config/database.yml`, define your databases:

```yaml
development:
primary:
adapter: postgresql
database: primary_db
username: user
password: password

secondary:
adapter: postgresql
database: secondary_db
username: user
password: password
```

2. In your model, establish the connection:

```ruby
class SecondaryModel < ApplicationRecord
self.abstract_class = true
establish_connection :secondary
end

class YourModel < SecondaryModel
# Your model code here
end
```

3. Use the models as needed, specifying which database to interact with.

Ruby On Rails

Ques:- Choosing between belongs_to and has_one?

Asked In :- bunq,

Right Answer:
Use `belongs_to` when the model contains the foreign key and is the child in the relationship. Use `has_one` when the model does not contain the foreign key and is the parent in the relationship.

Ruby On Rails

Ques:- What is bundler?

Asked In :- V2STech Solutions,

Right Answer:
Bundler is a Ruby tool that manages gem dependencies for your application, ensuring that the right versions of gems are installed and used consistently across different environments.

Ruby On Rails

Ques:- What are the servers supported by ruby on rails?

Asked In :-

Right Answer:
Ruby on Rails supports several servers, including Puma, Unicorn, WEBrick, and Passenger.

Ruby On Rails

Ques:- What are the different components of rails ?

Asked In :- Zysk Technologies,

Right Answer:
The different components of Rails are:

1. **Active Record** - Object-Relational Mapping (ORM) for database interactions.
2. **Action Pack** - Handles the controller and view layers (includes Action Controller and Action View).
3. **Action Mailer** - Manages email sending functionality.
4. **Active Job** - Framework for declaring jobs and making them run on a variety of queuing backends.
5. **Action Cable** - Integrates WebSockets for real-time features.
6. **Active Storage** - Manages file uploads and attachments.
7. **Action Text** - Handles rich text content and editing.
8. **Routing** - Manages URL routing to controllers and actions.

Ruby On Rails

Ques:- How do I find only duplicate entries in a database table?

Asked In :-

Right Answer:
You can find duplicate entries in a database table using a SQL query like this:

```sql
SELECT column_name, COUNT(*)
FROM table_name
GROUP BY column_name
HAVING COUNT(*) > 1;
```

Replace `column_name` with the name of the column you want to check for duplicates and `table_name` with the name of your table.

Ruby On Rails

Ques:- How many types of associations relationships does a model have?

Asked In :-

Right Answer:
A model in Ruby on Rails can have three types of associations: `belongs_to`, `has_one`, and `has_many`. Additionally, there is `has_many :through` and `has_and_belongs_to_many`.

Ruby On Rails

Ques:- What is the difference between delete and destroy ?

Asked In :- Orion Innovation,

Right Answer:
In Ruby on Rails, `delete` removes a record from the database without invoking any callbacks, while `destroy` removes a record and also triggers any associated callbacks, such as `before_destroy` and `after_destroy`.

Ruby On Rails

Ques:- What is a proc ?

Asked In :-

Right Answer:
A proc in Ruby is an object that encapsulates a block of code, allowing it to be stored in a variable and executed later. It can take arguments and maintain its own context (scope).

Ruby On Rails

Ques:- Write a program to show the functionality of request.xhr in ruby on rails ?

Asked In :-

Right Answer:
```ruby
class PostsController < ApplicationController
def create
@post = Post.new(post_params)
if @post.save
respond_to do |format|
format.html { redirect_to @post, notice: 'Post was successfully created.' }
format.js # This will render create.js.erb
end
else
respond_to do |format|
format.html { render :new }
format.js # This will render create.js.erb for error handling
end
end
end

private

def post_params
params.require(:post).permit(:title, :content)
end
end
```

```javascript
// create.js.erb
if (request.xhr?) {
// Handle the AJAX response
$('#posts').append('<%= j render @post %>');
} else {
// Handle non-AJAX response
window.location.href = '<%= post_path(@post

Ruby On Rails

Ques:- What are the different filters used in ruby on rails?

Asked In :-

Right Answer:
In Ruby on Rails, the different filters used are:

1. **before_action** - Runs before a controller action.
2. **after_action** - Runs after a controller action.
3. **around_action** - Wraps around a controller action, allowing code to run before and after the action.
4. **before_filter** - An alias for before_action (deprecated in Rails 5).
5. **after_filter** - An alias for after_action (deprecated in Rails 5).
6. **around_filter** - An alias for around_action (deprecated in Rails 5).

Ruby On Rails

Ques:- Mention the differences between the observers and callbacks in ruby on rails.

Asked In :-

Right Answer:
Observers are used to encapsulate the behavior that should happen in response to changes in a model, allowing for cleaner code separation. Callbacks, on the other hand, are methods that get called at certain points in an object's lifecycle (like before or after saving) and are defined within the model itself. Observers are typically used for external behavior, while callbacks are tightly coupled with the model's lifecycle events.

Ruby On Rails

Ques:- What do you understand by rails migration and what it can do?

Asked In :- CodeStore,

Right Answer:
Rails migration is a feature in Ruby on Rails that allows developers to make changes to the database schema over time in a consistent and easy way. It can create, modify, and delete database tables and columns, as well as manage indexes and constraints, all through Ruby code instead of raw SQL. Migrations help keep track of changes and allow for easy version control of the database structure.

Ruby On Rails

Ques:- What do you understand by rails?

Asked In :-

Right Answer:
Rails, or Ruby on Rails, is a web application framework written in the Ruby programming language. It follows the Model-View-Controller (MVC) architecture and emphasizes convention over configuration, making it easier to develop database-backed web applications quickly and efficiently.

Ruby On Rails

Ques:- write a program to show the usage of sql in the database file?

Asked In :-

Right Answer:
```ruby
# In a Ruby on Rails application, you can use ActiveRecord to interact with the database.
# Here’s a simple example of how to perform SQL operations using ActiveRecord.

# Assuming you have a model called Post
class Post < ApplicationRecord
end

# To create a new record
Post.create(title: 'My First Post', content: 'This is the content of my first post.')

# To retrieve all records
posts = Post.all

# To find a specific record by ID
post = Post.find(1)

# To update a record
post.update(title: 'Updated Title')

# To delete a record
post.destroy

# To execute raw SQL
ActiveRecord::Base.connection.execute("SELECT * FROM posts WHERE title = 'My First Post'")
```

The Ruby on Rails category on takluu.com is tailored for web developers and programmers preparing for interviews focused on the Ruby on Rails framework. Ruby on Rails, commonly known as RoR, is a powerful open-source web application framework written in Ruby, following the MVC architecture.

This section covers important topics such as Rails MVC components, routing, Active Record ORM, migrations, validations, callbacks, and RESTful APIs. You will also find interview questions related to Rails security best practices, testing frameworks like RSpec, and deployment strategies.

Interviewers typically ask practical questions such as:

“Explain the MVC pattern in Ruby on Rails.”
“How does Active Record simplify database interactions?”
“What are Rails migrations and why are they important?”

Our content breaks down complex Rails concepts into easy-to-understand explanations with code examples and real-world scenarios. Whether you’re a beginner or an experienced developer, this category helps you strengthen your knowledge and prepare confidently for interviews.

At Takluu, we regularly update the Ruby on Rails category with the latest features, security updates, and best practices to ensure you stay competitive in the fast-evolving web development field.

Questions in: Ruby On Rails

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