Django Interview Questions and Answers

By | October 6, 2021
Django Interview Questions and Answers

If you google for web development jobs, there, you will find most of them require Django skills. If you are preparing for an upcoming web developer interview, we would recommend you go through these best Django interview questions.

Django is the most popular, open-source and powerful Python web framework used for full-stack web development. With the increasing demand for Python, Django has also built extensive community support for itself.

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Django Interview Questions and Answers

Question: What is Django?

Answer: Django is a full-stack Python web framework that is used to create dynamic web applications.

Question: What is the latest version of Django?

Answer: The latest version of Django is 3.2 and it comes with Long Term Support(LTS).

Question: From where does Django got its name?

Answer: Django is named after Django Reinhardt, who was a gypsy jazz guitarist in the early 1930s.

Question: On which architecture design pattern Django works?

Answer: Django works on the MVT (Model View Templates) architecture.

Question: Give some advantages of using Django.

Answer:

  • It has a built-in web admin interface that can be used to handle models easily.
  • It has many pre-packaged APIs for common user tasks.
  • Offers easy database management.
  • It is a Python framework, so it has many libraries in inheritance.
  • It can develop applications very fast, and the build quality of the applications made on Django is just amazing.

Question: Give some features of Django.

Answer:

  • It has well-organized and complete web documentation.
  • It is SEO-friendly.
  • Supports form handling.
  • Can also work as a testing framework.
  • As a Python framework, it has a large community.
  • It can handle a large amount of data that shows its high scalability.
  • It is a full-stack web framework.
  • Admin Authentication Feature gives apps extra security.
  • Object-Relational-Mapping helps to create data using the native object-oriented programming language.
  • It provides an inbuilt admin interface.

Question: Give some disadvantages of Django.

Answer:

  • We have to specify the URL routing in Django for every view. The URL specifying syntax is complicated but it is common, nonetheless, for a beginner, it could be confusing at first.
  • Speed is a major disadvantage of python. So for Django with the increase in data, it slows down work.
  • Django is monolithic, which means that the entire programming should come under the MVT architecture. Hence, the developer does not have any control over the flow of Django.
  • It is not an ideal framework for developing minor projects.

Question: Why do we use the include() function in the project urls.py file?

Answer: We use the include() function to attach the app URLs file with the project URLs file. This is a way by which we can easily add different URLs of the different app with the project’s main URLs.

Question: Name all the types of inheritance possible in Django.

Answer:

  • Abstract base classes.
  • Multi-table inheritance.
  • Proxy models.

Question: What is a context in Django?

Answer: Context is an optional render() function attribute, which is a dictionary by nature and its key is used as a template tagging in templates file.

Question: If you have worked with Flask then give some differences between Flask and Django.

Answer:

Parameters Django Flask
Projects Used for big projects. Efficient with small projects.
Admin It comes with a robust admin panel. Here we need to design one.
Learning Curve It has a high learning curve because it contains many features. It is very easy to learn because it does not offer too much.
Debugging Supports visual debugging. There is no support for visual debugging.
Framework type Full-stack framework. Micro framework.

Question: How to install Django in your system?

Answer: Django is a python package so we can use the pip command to install Django. For example:

C:\Users> pip install Django

Question: How to create a Django project?

Answer: To create a Django Project we need to open the command prompt and write this command:

django-admin startproject project_name

This will create a directory with the project_name having a subdirectory and a manage.py file.

Question: By default which database does Django follow?

Answer: By default, Django has SQLite, but if we want, we can change it with MySQL or any other relational database from the setting.py file.

Question: Where do we register our models?

Answer: We need to register our models at the admin.py file.

Question: What does the createsuperuser subcommand do?

Answer: The createsuperuser command creates a super user, who can access the admin interface of the app.

Question: Name the caching strategies in Django.

Answer:

  • File System caching
  • In-memory caching
  • Memcached
  • Database caching

Question: What is the use of manage.py in Django?

Answer: The manage.py file is created automatically when we create Django project with the Django-admin start project. It has the following uses:

  • Put our projects packages on sys.path.
  • Set a Django environment.
  • Features a collection of subcommands used to run all Django modules.

Question: What parameters do we use in signals?

Answer:

  • Receiver
  • Sender

Question: Name the usages of middlewares in Django.

Answer:

  • Session management.
  • User authentication.
  • Cross-site request.
  • Forgery protection.
  • Content gzipping.

Question: Give some drawbacks of Object Relational Mapping in Django?

Answer: Its implementation is quite complex and with a huge amount of data it also affects the speed of Django.

Question: Why do we use the migration subcommand?

Answer: We use the migration subcommand to tell the Django that we have made some changes in the Model database and it needs to update those.

Question: Why do we use the makemigration subcommand?

Answer: By running the makemigration command we tell Django that we have made some changes in our models and we would like these to be stored as a migration.

Question: What does the session framework do?

Answer: The session framework lets us store and retrieve arbitrary data on a pre-site-visitor basis. It stores data on the server-side and abstracts the sending and receiving of cookies.

Questions: Name all the manage.py subcommands.

Answer: 

auth

  • changepassword
  • createsuperuser
  • contenttypes
  • remove_stale_contenttypes

django

  • check
  • compilemessages
  • createcachetable
  • dbshell
  • diffsettings
  • dumpdata
  • flush
  • inspectdb
  • loaddata
  • makemessages
  • makemigrations
  • migrate
  • sendtestemail
  • shell
  • showmigrations
  • sqlflush
  • sqlmigrate
  • sqlsequencereset
  • squashmigrations
  • startapp
  • startproject
  • test
  • testserver

sessions

  • clearsessions

staticfiles

  • collectstatic
  • findstatic
  • runserver

Question: Name some common Django exceptions.

Answer:

  • AppRegistryNotRead
  • ObjectDoesNotExist
  • EmptyResultSet
  • FieldDoesNotExist
  • MultiObjectReturned
  • SuspiciousOperation
  • PermisssionDenied
  • ViewDoesNotExist
  • MiddlewareNotUsed
  • FieldError
  • ValidationError

Question: How can we register a model in Django?

Answer: We register our models at the admin.py file. To register the model we use the admin.site.register(model_name) command.

Question: What do you know about ‘django-admin’?

Answer: It is a Django command-line utility that can be used by the administrator for various tasks. From creating a new project to make migrations, django-admin can perform all the major tasks that can be performed by manage.py. Here is the list of major django-admin commands:

Commands Description
django-admin startproject project_name Creates a Django-based project.
django-admin help It lists all the information about the django-admin command line.
django-admin help -command Lists out all the django-admin commands.
django-admin version Shows the current version of Django.
django-admin makemigrations Makes new migrations if there are changes in the project or app model.
django-admin runserver Runs the development server.
django-admin shell Opens an interactive shell.
django-admin startapp Creates a new app directory.

Question: What are the models in Django?

Answer: Django models can be treated as a source of information about the data. Also, each model represents a database table, and its attributes represent database fields.

In Django, models play a vital role because they provide an easy and optimized way to create databases. Django models also provide APIs to communicate, structure and manipulate the data.

Question: What are views in Django?

Answer: The view contains the main logic and functions about what to accept and what to show the user. Moreover, it deals with the HTTP request and sends back the appropriate response.

In response, the view could send anything such as HTML content, redirect notification, a message, an error, XML document, and an image. As Django works on the MVT architecture, it allows the view to communicate with the app model or database.

Question: What are templates in Django?

Answer: Templates are the static part of the Django web applications. A template could be a collection of various text documents, which include HTML, CSS, and JavaScript. The template renders the information that is sent from the view section of the application.

Question: What is the difference between a Django project and a Django app?

Answer: A Django project could have one or more than one application. A project is a collection of apps, whereas a Django app is a simple web application that is supposed to perform some special functions in order to interact with the user.

Question: What are static files in Django?

Answer: These are the additional files that are used to make the web application more interactive. Basically, it is a static file containing different additional files, such as CSS, images, and JavaScript. Also, Django has an inbuilt static engine to manage all these static files.

Question: What are Django mixins?

Answer: mixins are the classes predefined in Django, which are used to provide discrete functionalities. The sole purpose of mixins is to make the code reusable and increase the Django DRY property.

Question: What do you know about Django sessions?

Answer: Django provides inbuilt support for sessions, which can be used to collect and show arbitrary data based on user visits. The main task of these sessions is to store data on the server-side, which can be sent and received between the server and the user through cookies.

Question: How Django deals with cache?

Answer: In general, the cache provides an alternative approach to reduce the expense of creating the same dynamic page again and again on each request by the same user. Django also provides an inbuilt cache system that allows the user to save the dynamic page, so with repetitive requests, the engine does not need to recalculate the same page.

Django can deal with various types of caches, which include downstream and browser-based cache, but the developer does not get full control over the cache.

Question: What is the use of the migrate command?

Answer: If we make changes in the Django models then we need the migrate command to propagate those changes. With the help of the migrate command, we can apply and un-apply the migrations. A migration in Django can be treated as version control for its models.

If a project contains more than one application then we can migrate the specific model by mentioning the application name. If making migration we do not mention the app name then migration will perform on every model of the project.

Question: What are the commands to get and filter data from the database?

Answer: In Django, we have ORM (Object Relation Mapping), which can be used to access data from the database using simple Python commands. To get all the data from a database, we can use the .object.all() command:

database_object.objects.all()

To get specific data we can use the filter and get methods.

database_object.objects.filter(pk=12)
#or 
database_object.object.get(name="Sahil")

Question: How does Django proceed request?

Answer: 

  • First, Django determines if the URL is valid or not.
  • If the URL is valid then the corresponding view module is loaded according to the URL pattern.
  • After that, the view module is executed by the interpreter, and an appropriate response is sent to the user.

Question: Create a view that displays heading 1 “TechGeekBuzz”, without using a template or HTML document.

Answer:

from django.http import HttpResponse def hello_world(request):     data = "<h1>TechGeekBuzz</h1>"     return HttpResponse(html)

Questions: List some Django exceptions.

Answer:

Exception Description
AppRegistryNotReady This exception occurs when we try to access the model without registering it.
ObjectDoesNotExist It raises when you try to access an invalid class.
EmptyResultSet This exception arises when the query does not return any result.
FieldDoesNotExit This exception rises when you mention an invalid field value in the metadata fields list.
MultipleObjectReturned This exception occurs if the function is supposed to accept one object and multiple objects are returned.

Question: How stable is Django?

Answer: Django is pretty stable. Even various popular applications, such as Instagram and Pinterest are completely built on Django. The Python web framework also provides a regular annual update to stay relevant in the market of web frameworks.

With each new update, Django introduces a slew of changes. With time, Django has gained too much popularity, and now many web projects and robust back-end applications are built on it.

Question: Do we need a specific python version to work with Django?

Answer: No, we can use any Django version with any Python version, but there are some highly-recommended version match-ups that:

Python Versions Django Versions
1.11 2.7, 3.4, 3.5, 3.6 and 3.7
2.0 3.4, 3.5, 3.6, and 3.7
2.1, 2.2 3.5, 3.6, and 3.7
3.0 3.6, 3.7 and 3.8

Question: Can we use NoSQL instead of SQL with Django?

Answer: Django originally supports the SQL database system, such as PostgreSQL, MySQL, and SQLite but with the help of some third-party tools we can integrate NoSQL with Django.

Question: How can we use the file-based session in Django?

Answer: To use the file-based session in the settings, we need to set the SESSION_ENGINE to "django.contrib.sessions.backends.file".

Question: Is Django a Content Management System (CMS)?

Answer: No, it is not a CMS. It is a Python web framework, however, we can use it to built CMS applications.

Question: What is csrf_token?

Answer: CSRF stands for Cross-Site Request Forgeries, and it is a protection used with Django forms to fight against malicious attacks.

Question: Can a Django model have multiple primary keys?

Answer: No, In Django models, we can only have a single column for the primary key.

Question: What commands we can use to see the raw queries running by Django?

Answer: In the Command shell run the following command:

from django.db import connection
connection.queries

Question: What is Serialization?

Answer: In Django, using the concept of serialization, we can convert the model’s data into other transferable data formats such as XML and JSON.

Question: What is DjangoRestFramework?

Answer: It is a Django toolkit that can be used to build robust REST APIs. It comes with authentication policies that include packages like OAuth1a and OAuth2. It can be installed using the following python-pip command:

pip install djangorestframework

Conclusion

With this, we have reached the end of our Django interview questions and answers. We hope you find these questions relevant to read before appearing for a web developer interview.

If you have appeared in any Django interview in the last few months, please comment down the technical questions you tackled during the interview. If you like these Django interview questions or have any suggestions please let us know by commenting down below.

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Author: Paridhi Joshi

Paridhi Joshi is an expert web content manager with significant experience in content creation. Professionally she is dedicated to staying up to date with the latest trends and technologies in content writing and committed to bringing state-of-the-art web approaches to the workplace. She is an efficient multi-tasker who can complete multiple projects under strict deadlines.

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