Django prefetch_与限制相关

使用Django中的prefetch_related方法可以优化数据库查询，提高网站的性能。prefetch_related方法可以一次性获取多个关联对象，减少了数据库的查询次数，提高了查询效率。在某些情况下，使用prefetch_related方法可以大幅度减少查询时间。

python
from django.db import models
class Category(models.Model):
    name = models.CharField(max_length=50)
class Article(models.Model):
    title = models.CharField(max_length=100)
    content = models.TextField()
    category = models.ForeignKey(Category, on_delete=models.CASCADE)
articles = Article.objects.prefetch_related('category')

python
from django.db import models
class Author(models.Model):
    name = models.CharField(max_length=50)
class Book(models.Model):
    title = models.CharField(max_length=100)
    author = models.ForeignKey(Author, on_delete=models.CASCADE)
authors = Author.objects.prefetch_related('book_set')
for author in authors:
    print(f"作者：{author.name}")
    print("图书列表：")
    for book in author.book_set.all():
        print(book.title)