DataTerrain Python and Django Developer Interview Questions, Process, and Tips

Decorators in Django are used to modify the behavior of functions or methods. @login_required ensures user authentication, while @permission_required checks for specific permissions.

• Decorators are functions that wrap another function to modify its behavior.

• @login_required decorator ensures that the user is authenticated before accessing a view.

• @permission_required decorator checks if the user has specific permissions b...read more

To revert changes made in Django migrations, use the command 'python manage.py migrate <app_name> <migration_name>'.

• Use the command 'python manage.py showmigrations' to list all migrations and their names.

• Identify the migration name you want to revert (e.g., 'app_name', '0002_migration_name').

• Run the command 'python manage.py migrate <app_name> <migration_name>' to revert the specific migration.

To fetch API data in Django from server using params dynamically.

• Use Django's HttpRequest object to access query parameters

• Extract the query parameter value using request.GET.get('querydata')

• Use the extracted value to dynamically fetch data from the server

Class-based views are based on classes and provide more structure and functionality, while function-based views are based on functions and are simpler and more flexible.

• Class-based views are defined as classes and inherit from Django's generic view classes, providing built-in functionality such as mixins and decorators.

• Function-based views are defined as functions and are more flexible, allowing for custom logic and co...read more

SQL Procedures are stored SQL code that can be executed on demand. Triggers are special types of stored procedures that are automatically executed when certain events occur.

• SQL Procedures are reusable blocks of SQL code that can be called by other programs or scripts.

• Triggers are special types of stored procedures that are automatically executed when specific events occur in the database.

• Triggers are commonly used for ...read more

Django supports multiple databases through its database router feature.

• Django allows defining multiple database connections in settings.py

• Use database routers to route specific models to different databases

• Example: routing user data to a separate database for better performance

REST API is a set of rules and conventions for building and interacting with web services.

• REST stands for Representational State Transfer

• Methods available in REST API are GET, POST, PUT, DELETE

• GET - Used to retrieve data from a server

• POST - Used to send data to a server to create a new resource

• PUT - Used to update an existing resource on the server

• DELETE - Used to remove a resource from the server

• Example: GET request t

Custom middleware in Django allows for processing requests and responses before reaching views.

• Custom middleware is a Python class that defines methods to process requests and responses in Django.

• To create custom middleware, define a class with methods like process_request, process_response, etc.

• Register the custom middleware in the Django settings.py file under the MIDDLEWARE key.

• Example code: class CustomMiddleware: ...read more

Message queues and caching systems are used to improve performance and scalability in web applications.

• Message queues help in decoupling components by allowing asynchronous communication between them.

• Caching systems store frequently accessed data in memory to reduce database load and improve response times.

• Popular message queue systems include RabbitMQ, Kafka, and Redis.

• Common caching systems include Memcached and Redi...read more