Можете объяснить, что такое QuerySet в рамках Django и как он используется для взаимодействия с базой данных?

In Django, a QuerySet is an object representing a set of records from the database that match a specific query. It allows for convenient and efficient interaction with the database through ORM.

Main features of QuerySet:

• Lazy execution: the database query is performed only when necessary (e.g., during iteration or conversion to a list).
• Support for filtering, sorting, aggregation, and other operations via methods like filter(), exclude(), order_by().
• Methods can be combined and chained to build complex queries.

Example usage:

from myapp.models import Product

# Get all products with a price greater than 100
expensive_products = Product.objects.filter(price__gt=100)

for product in expensive_products:
    print(product.name, product.price)

Thus, QuerySet is the main tool for working with data in Django, enabling expressive and efficient database queries without direct SQL.