class Book(models.Model):nid = models.AutoField(primary_key=True)title = models.CharField(max_length=32, default=None)create_time = models.DateTimeField()price = models.DecimalField(decimal_places=2, max_digits=8, default=None)publish_id = models.ForeignKey(to="Publish", on_delete=models.CASCADE)authors = models.ManyToManyField(to='Author')def __str__(self):return str(self.nid) + ':' + self.titleclass Publish(models.Model):nid = models.AutoField(primary_key=True)name = models.CharField(max_length=32)email = models.CharField(max_length=32)class Author(models.Model):name = models.CharField(max_length=32)age = models.IntegerField()email = models.CharField(max_length=32)ad = models.OneToOneField(to="AuthorDetail", on_delete=models.CASCADE)class AuthorDetail(models.Model):address = models.CharField(max_length=32)telephone = models.IntegerField()

book_list = []for i in range(100):book = Book(title='book_%s' % i, price=i * i)book_list.append(book)Book.objects.bulk_create(book_list)

# 一对多添加用户
publish = Publish.objects.get(nid=1)
Book.objects.create( title='ubuntu',price=122, create_time='2012-2-2', publish_id=publish, # publish_id_id=publish.nid  )
# 多对多添加用户
author01 = Author.objects.get(id="1")
author02 = Author.objects.get(id="2")book = Book.objects.get(nid='2')
# book.authors.add(author01, author02)
# 多对多第二种
book.authors.add(1, 2)
# 多对多第三种
book.authors.add(*[1, 2])
# 删除关联的作者
 book.authors.remove(author01)
# 删除所有关联的作者
 book.authors.clear()
# 先删除所有在绑定
book.authors.set(1)

# 一对多查询# 正查book = Book.objects.get(nid='1')# 取到关联的对象publish = book.publish_idprint(publish.name)# 反查publish = Publish.objects.get(nid='1')books = publish.book_set.all()# 多对多查询book = Book.objects.get(nid='1')authors = book.authors.all()author = Author.objects.get(id='1')book = author.book_set.all()# 一对一author = Author.objects.get(id='1')ad = author.adauthor_detail = AuthorDetail.objects.get(id='1')author = author_detail.author

# linux这本书的出版社名字# 正向name = Book.objects.filter(title='linux').values('publish_id__name')# 反向name = Publish.objects.filter(book__title='linux').values('name')# 查询第一个出版社对用的所有书# 正向book = Publish.objects.filter(nid='1').values('book__title')# 反向book = Book.objects.filter(publish_id_id='1').values('title')# 查询Linux这本书所有作者的手机号telephone = Book.objects.filter(title='linux').values('authors__ad__telephone')telephone = Author.objects.filter(book__title='linux').values('ad__telephone')# 查询id=1的出版社的作者的书籍和作者的名字title_name = Publish.objects.filter(nid='1').values('book__authors__name', 'book__title')title_name = Book.objects.filter(publish_id_id=1).values('title', 'authors__name')# 查询作者手机号的开头为110的书籍和出版社名称title_name = Author.objects.filter(ad__address__startswith='北京').values('book__title', 'book__publish_id__name')

from django.db.models import Avg, Max, Sum, Min, Countavg = Book.objects.all().aggregate(price=Avg('price'))# 单表分组查询# 查询每个出版社id以及对应大的书籍个数count = Book.objects.values('publish_id').annotate(count=Count(1))# values中的值为分类的参数'''select Count(1) from Book GROUP by publish_id'''# 跨表分组查询# 查看每一个出版社名称以及对应的书籍个数count = Book.objects.values('publish_id__name').annotate(count=Count(1))count = Publish.objects.values('name').annotate(c=Count('book__nid'))# 查找作者大于一个的书籍对应的作者数query = Book.objects.annotate(c=Count('authors')).filter(c__gt=1).values('c', 'title')