Django Interview Questions

Django is a high-level Python web framework that promotes rapid development and clean, pragmatic design. It’s popular because of its built-in admin interface, ORM, security features, scalability, and "batteries-included" philosophy.

• Async view support
• Type annotations in views and models
• Redis cache backend enhancements
• Better ORM performance
• Support for Python 3.12
• Streaming HTTP responses with async views

• Model: Defines the data structure (database schema)
• View: Handles business logic and user requests
• Template: Handles presentation logic (HTML rendering)

Django ORM maps Python classes to database tables. It allows developers to write database queries using Python methods instead of raw SQL.

User.objects.filter(is_active=True)

A QuerySet is a collection of database queries constructed using Django’s ORM. It’s lazy, meaning it doesn’t hit the DB until needed.

Middleware is a layer that processes requests and responses globally before reaching views or returning to the browser. Examples include authentication, session, and security middlewares.

By extending AbstractBaseUser and BaseUserManager, and updating AUTH_USER_MODEL in settings.py.

• null=True: Database can store NULL (used at DB level)
• blank=True: Field can be left empty in forms (used at validation level)

• Static files (CSS, JS): Managed with STATIC_URL, STATICFILES_DIRS
• Media files (user uploads): Managed with MEDIA_URL, MEDIA_ROOT

DRF is used to build Web APIs in Django. It provides:

• Serializers for converting data
• ViewSets and Routers
• Built-in authentication
• Browsable API interface

• FBV: Simple and explicit
• CBV: More abstract, reusable, supports mixins and inheritance
Copy code

class MyView(View):     
     Def get(self, request): ... 

Using Form and ModelForm classes which validate user input through the clean() and clean_() methods.

Signals allow decoupled components to get notified when actions occur (e.g., post_save, pre_delete). They are useful for side effects like sending emails.

• CSRF protection
• XSS and clickjacking protection
• SQL injection prevention via ORM

Since Django 3.1+, views can be defined using async def, allowing non-blocking I/O and integration with asyncio, useful for APIs and websockets.

Django supports various cache backends like:

• In-memory (locmem)
• Memcached
• Redis

Use cache.set() and cache.get() or per-view caching decorators.

Use:

python manage.py makemigrations 
Python manage.py migrate 

This creates and applies schema changes to the database.

It provides an auto-generated, customizable interface to manage site data based on registered models — useful for internal tools or CMS.

A context processor is a function that injects global variables into templates, such as current user or site settings.

• Use WSGI/ASGI (e.g., with Gunicorn or Daphne)
• Set DEBUG = False
• Use a production-ready database (e.g., PostgreSQL)
• Serve static/media files via Nginx
• Use environment variables for secrets
• Secure with HTTPS and proper headers