50 Top Django Interview Questions and Answers

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50 Top Django Interview Questions and Answers
vinaykhatri

Vinay Khatri
Last updated on March 28, 2024

    If you google web development jobs, 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 received extensive community support.

    Django Interview Questions and Answers

    Let us discuss some commonly asked Django interview questions, along with their answers. We shall divide the entire set of Django interview questions into three levels, namely basic-level Django interview questions, intermediate-level Django interview questions, and advanced-level Django interview questions.

    Django Interview Questions for Freshers

    1. What is Django?

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

    2. What is the latest version of Django?

    Answer: The latest version of Django is 3.2.9, and it comes with Long Term Support (LTS).

    To check the django version installed for your Python environment use the following command.

    >>> import django
    >>> django.__version__
    '4.0.3'

    3. From where does Django get its name?

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

    4. On which architecture design pattern does Django work?

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

    5. 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.
    • The Python framework offers easy database management.
    • It is a Python framework, so it has many libraries.
    • Django can develop applications very fast, and the build quality of the applications made on Django is just amazing.

    6. Explain the Django Architecture.

    Answer:
    Django uses the MVT(Model View Template) architecture, which is similar to the popular MVC (Model View Controller) architecture used by other popular frameworks like ruby on rails, ASP.NET, Spring, etc.
    In Model View Template architecture, Django uses Models for Database schemas, Views to process requests and logic, and Template to return & render data or HTML pages to the client.

    7. Explain the Django project directory structure.

    Answer:
    After we create a Django project using the command

    django-admin startproject myProj

    We get the following project directory structure.

    myProj/
        manage.py
        myProj/
            __init__.py
            settings.py
            urls.py
            asgi.py
            wsgi.py
    • The manage.py is a command-line utility, and we can use it to interact with the Django projects and perform various tasks, including creating apps, running local development, managing static files, etc.
    • myProj/ is the directory for the project, and its name is similar to the project name.
    • myProj/__init__.py is the empty python file that tells Python to treat myProj directory as a Python Package rather than a simple directory.
    • myProj/settings.py file contains the configuration or settings for the project.
    • myProj/urls.py file contains the valid URLs for all the pages of the web page. This file is a kind of table of content for the website powered by Django.
    • myProj/asgi.py file works as an Asynchronous Server Gateway Interface entry point for the ASGI-compatible web servers. This file was introduced in django3.0.
    • myProj/wsgi.py file acts as an entry point for the WSGI-compatible webserver.

    Note : asgi.py and wsgi.py files are used by the webservers to deploy the project on the server.

    8. Give some features of Django .

    Answer:

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

    9. 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, an increase in data slows down the output.
    • 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.

    10. What are Django URLs?

    Answer:
    The Django URLs are used to map the specified website path to the View. We can use the URLs to module the project into different apps. For example, we can have multiple apps in a project, and according to the app, we can define the URLs, For example, if a project has two apps blogs and tools we can specify two different URLs such as example.com/blogs/ and example.com/tools/.
    The project comes with the default urls.py file which is the main file for URLs, we can also create a urls.py file for the individual apps for the modular section.

    Syntax:

    from django.contrib import admin
    from django.urls import path,include
    urlpatterns = [
        path('admin/', admin.site.urls),
        path("leads/", include(blog.urls', namespace="blog")),
        path("leads/", include(tool.urls', namespace="tool")),]


    11. 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 different apps with the project's main URLs.

    Example :

    from django.urls import path,include
    urlpatterns = [   
        path("leads/", include(blog.urls', namespace="blog")),
    ]

    12. Name all the types of modal inheritance possible in Django.
    Answer:
    Abstract base classes inheritance
    : This inheritance is used when we want to put a common information in a specific modal, and we inherit that common modal in other modals.
    Example

    from django.db import models
    class Subjects(models.Model):
        name= models.CharField(max_length=100)
        total_classes= models.PositiveIntegerField()
     
        class Meta:
            abstract = True
     
    class Student(Subjects):
        name= models.CharField(max_length=5)


    The abstract class does not create a table in the database, Instated the inherited class does with the abstract class field inherited.

    Multi-table inheritance: The multi-table inheritance is similar to the Python inheritance . In this inheritance both parent’s and child’s tables are created in the database.

    from django.db import models
    class Station(models.Model):
        name = models.CharField(max_length=50)
        address = models.CharField(max_length=80)
     
    class Service(Place):
        car_service = models.BooleanField(default=False)
        bus_service = models.BooleanField(default=False)


    Proxy models: Proxy models are used when we do not directly want to change the original modal. In the proxy modal, we inherited from an original modal, and in the proxy modal we can make all the changes and later delete them, this will have no effect on the original modal.
    Example

    from django.db import models
    class Student(models.Model):
        first_name = models.CharField(max_length=30)
        last_name = models.CharField(max_length=30)
     
    class MyStudent(Student):
        class Meta:
            proxy = True
     
        def do_something(self):
            # ...
            pass


    13. What is the 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 the templates file.

    from django.shortcuts import render
    def index(request):
        #context
        context["Message"] = "Hello World"
        return render(request, 'index.html', context=context)
    
    

    14. 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. Flask is very easy to learn because it does not offer too many features.
    Debugging Supports visual debugging. There is no support for visual debugging.
    Framework type Full-stack framework. Microframework.

    15. How to install Django in your system?

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

    pip install Django

    16. How to create a Django project?

    Answer: To create a project in Django, 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 name having a subdirectory and a manage.py file.

    17. 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.

    18. Where do we register our models?

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

    19. What does the createsuperuser command do?

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

    20. Name the caching strategies in Django.

    Answer:

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

    21. What is the use of manage.py in Django?

    Answer: The manage.py file is created automatically when we create a 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.

    22. What parameters do we use in signals?

    Answer:

    • Receiver
    • Sender

    23. Name the usages of middleware in Django.

    Answer:

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

    Intermediate-level Django Interview Questions

    24. What is django ORM?
    Answer:

    ORM stands for Object Relational Mapping, and it is one of the most important concepts/tools of Django. In Django, we do interact with the SQL database, by creating, retrieving, updating, and deleting data between the database, without writing the raw SQL queries. The Django ORM  allow us to interact with the SQL database by writing Python code.
    For example to retrieve all the detail from a data base we write the following SQL code

    SELECT * FROM Article
    

    In Django, we write

    all_articles = Article.objects.all()
    

    25. 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.

    26. Why do we use the migration subcommand?

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

    27. Why do we use the makemigrations subcommand?

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

    28. What does the session framework do?

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

    29. What is django -admin and manage.py. Name all the manage.py subcommands.

    Answer:
    django-admin
    is a command-line utility, and it is used to perform the administrator task related to Django project. We can use the django-admin command to create a new project or create new apps in the existing project.
    Example

    django-admin startproject mywebsite
    


    manage.py is also a command-line utility, and it is created automatically after we create a django project using the django-admin startproject command. It can also perform the same task as djagno-admin.

    python manage.py startapp blog
    


    In Django, we only mostly use the django-admin command to create the project, and manage.py command to perform the rest of the project tasks.
    There are various sub-commands associated with Django-admin and manage.py.

    auth
    changepassword: Using this command we can change the password of a username.

    python manage.py changepassword [<username>]


    createsuperuser: This command create a superuser or admin user for the project.

    python manage.py createsuperuser
    

    django
    check: command is used to inspect the Django project or individual apps for the common problem.

    django-admin check 
    

    compilemessages: command compiles the “.co” which are created by makemessage command.

    django-admin compilemessages --locale=pt_BR
    


    createcachetable: This command creates cache tables, for the use of the database cache backend.

    django-admin createcachetable
    


    dbshell:
    It runs the command-line client for the specified database engine.

    django-admin dbshell
    

    diffsettings: This command is used to display the difference between the current setting file and the default setting file.

    python manage.py diffsettings
    

    dumpdata: This command is used to export all the data in the database in a specific format.

    python manage.py dumpdata > backup.json
    

    By default the dumpdata export data in json format we can also the data in different formats such as:

    • XML
    • Jsonal
    • yaml

    We than later use load the data using the loaddata subcommand.
    flush: This command can remove all the data from the database.

    python manage.py flush
    

    inspectdb: This command show all the models or database defined in the project.

    python manage.py inspectdb
    

    loaddata: This command is used to load data into the database.

    python manage.py loaddata backup.json
    

    makemessages: This command can scan all the files in the directory tree and pull out all the strings marked for translation and write them into .mo files.

    python manage.py makemessages 
    

    makemigrations: This command makes the migration based on the changes made to the models.

    python manage.py makemigrations 
    

    migrate: After making the migrations the migrate command synchronizes the database state with the current migrations.

    python manage.py migrate


    sendtestemail: This command is used to check if the sending mail function in Django is working or not. This command sends a testing mail to the specified recipients.

    python manage.py sendtestemail user@example.com
    

    shell: It start an interactive Python interpreter where we can interact with Django functions and models using Python

    python manage.py shell
    

    showmigrations: It can list all the migrations applied on the models.

    python manage.py showmigrations
    

    sqlflush: It prints the SQL command that is used to flush the data from the database.

    python manage.py sqlflush
    

    sqlmigrate: It shows the SQL commands used for the specific migration.

    python manage.py sqlmigrate auth 0001_initial
    

    sqlsequencereset: It shows the SQL command for resetting sequences for the given app

    python manage.py sqlsequencereset blog
    

    squashmigrations: It Squashes the migrations for an app from starting migration to the specified migrations.

    python manage.py squashmigrations auth 0001_initial 0008_alter_user_username_max_length
    

    startapp: This command is used to create a new app.

    python manage.py startapp app_name

    startproject: This command is used to create new Project

    django-admin startproject mywebsite
    

    test : This command run the teses for the installed app.

    python manage.py test 
    

    testserver: This command run a django development server same as runserver, but based on the specified features.

    python manage.py testserver features.json
    

    sessions
    clearsessions
    : This command is used to clean out all the expired sessions.

    python manage.py clearsessions


    staticfiles
    collectstatic : This command move all the static files in the static root directory

    python manage.py collectstatic


    runserver : This command start a lightweight local development web server for the project.

    python manage.py runserver
    

    30. Name some common Django exceptions.

    Answer:

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

    31. How can we register a model in Django?

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

    32. 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 making 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.

    33. 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.
    We can define the models for individual apps inside the app directory models.py file.
    Example

    from django.db import models
    from django.utils import timezone
    class Post(models.Model):
        title = models.CharField(max_length= 200, unique=True)
        content = models.TextField(blank=True, null=True)
        date_posted = models.DateTimeField(default= timezone.now)
        author = models.ForeignKey(User, on_delete= models.SET_NULL,blank=True, null=True, related_name='posts')
        slug = models.SlugField(max_length=200,unique=True, verbose_name="URL", blank=True , null=True, help_text="Please enter the url for the blog eg python-introduction ")
        featured_image = models.ImageField(upload_to='post_images', blank=True, verbose_name='Featured Image')
    class Meta:
            verbose_name_plural  = "All Posts"
            ordering = ['-date_posted']
    def __str__(self):
            return self.title
    

    34. What are the 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, an XML document, and an image. As Django works on the MVT architecture, it allows the view to communicate with the app model or database.
    There are two ways by which we can write a Django view
    Class-based View

    from django.views.generic import TemplateView
    class Homepage(TemplateView):
        template_name = "index.html"


    Function-based View

    from django.shortcuts import render
    def homepage(request):
        return render(request,"index.html" )


    35. 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.

    36. 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, on the other hand, is a collection of apps. Also, a Django app is a simple web application that is supposed to perform some special functions in order to interact with the user.

    37. 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.

    Learn How to manage static files in django

    Django Interview Questions for Experienced Developers

    38. 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.

    39. 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.

    40. How does Django deal 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.

    41. 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. While making the migration, if we do not mention the app name, then migration will perform on every model of the project.

    42. 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")

    43. How to combine multiple QuerySets in Django.
    Answer:

    To combine two querysets in Django we can use the itertool chain method.

    from itertools import chain
    result_list = list(chain(blogs, users))


    44. How can we perform the OR operation in Django query.
    Answer:

    To perform the OR operation in the Django query we can use the Q object. The filter() function uses the comma (,) for the AND operation, but for the OR operation, we have to use the Q object with the pipe | operator.
    Example

    from blog.models import Product
    from django.db.models import Q
     
    men_or_women = Product.objects.filter(Q(title__icontains ="Men")|Q(title__icontains="Women"))


    45. How does Django proceeds a 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.

    46. 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)

    47. 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 Django 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.

    48. 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. Also, with time, Django has gained too much popularity, and now many web projects and robust back-end applications are built on it.

    49. 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. These are:

    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

    50. 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.

    51. 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" .

    52. 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 build CMS applications.

    53. 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.

    <form action="/update" method="POST">
        {%csrf_token%}
    </form>

    54. Can a Django model have multiple primary keys?

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

    55. What commands can we 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

    56. 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.

    57. 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 list. 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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    FAQs


    A Django developer is a professional responsible for creating and maintaining websites using the Django framework. They also detect bottlenecks in code and fix them immediately.

    Django developers are proficient in Python programming and possess a good understanding of system programming, GUI, web script development, rapid prototype development, and mathematics and scientific calculations. Additional skills include databases, such as MySQL and PostgreSQL, front-end development, Git, and testing.

    Yes, Django is a full-stack framework. It provides all features and tools required to develop a complete fully-functional website.

    The web development industry is booming more than ever before since businesses are going digital. And with Django being one of the most popular full-stack frameworks for web development, learning it would open up multiple job options.

    First, learn Python in-depth and earn proficiency in it. Make yourself acquainted with Django, start with simple concepts, and then move on to complex ones. Gain hands-on experience working with Django by developing web projects. This entire process will help you prepare for a Django interview. Besides, you can refer to the above list of Django interview questions to prepare for interviews.

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