一.关于content_type 使用
1.引入模块在models
from django.db import models from django.contrib.contenttypes.models import ContentType #使用ContentType from django.contrib.contenttypes.fields import GenericForeignKey, GenericRelation #正向查询, 反向查询
2. 创建数据库,普通课程, 私人课程, 价格策略
from django.db import models from django.contrib.contenttypes.models import ContentType from django.contrib.contenttypes.fields import GenericForeignKey, GenericRelation class Course(models.Model): title = models.CharField(max_length=32) price_policy_list = GenericRelation("PricePolicy") #只是为了反向查询 class DegreeCourse(models.Model): title = models.CharField(max_length=32) price_policy_list = GenericRelation("PricePolicy") #只是为了反向查询 class PricePolicy(models.Model): """ 价格策略 """ price = models.IntegerField() period = models.IntegerField() content_type = models.ForeignKey(ContentType, verbose_name="关联的表名称",on_delete=models.CASCADE) object_id = models.IntegerField(verbose_name="关联表的数据行ID") content_object = GenericForeignKey("content_type", "object_id") #通过找到content_type 找到 关联的表名, object_id 找到行id
最后创建数据库
3.在test.views 增加,反向查询
def test(request): obj = models.DegreeCourse.objects.filter(title="老人与海").first()#找到对象 models.PricePolicy.objects.create(price=9.9, period=30, content_object=obj)# content_object=obj obj2 = models.DegreeCourse.objects.filter(title="老人与海").first() models.PricePolicy.objects.create(price=19.9, period=30, content_object=obj2) obj3 = models.DegreeCourse.objects.filter(title="老人与海").first() models.PricePolicy.objects.create(price=29.9, period=30, content_object=obj3) # 反向查询 course = models.DegreeCourse.objects.filter(id=1).first() price_policys = course.price_policy_list.all() print(price_policys) return HttpResponse("OK")
结果
文章引用 https://www.cnblogs.com/c-x-m/articles/8991616.html#autoid-0-0-0
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