return u"%s the place" % self.name class Restaurant(models.Model): place= models.OneToOneField(Place) serves_hot_dogs = models.BooleanField() serves_pizza = models.BooleanField() def __unicode__(self): return u"%s the restaurant" % self.place.name 对应的数据库表结构是(after migration): ...
caption= models.CharField(max_length=32)def__unicode__(self):returnself.caption#用户表classUser(models.Model): username= models.CharField(max_length=32) #user_group为对象,对应UserGroup中的一行数据user_group=models.ForeignKey(UserGroup)def__unicode__(self):returnself.hostname forms模块中的foreign...
If True, this field is the primary key for the model. If you don’t specify primary_key=True for any fields in your model, Django will automatically add a field to hold the primary key, so you don’t need to set primary_key=True on any of your fields unless you want to override ...
classLegacyModel(models.Model):classMeta:db_table='"name_left_in_lowercase"'classForeignModel(models.Model):classMeta:db_table='"OTHER_USER"."NAME_ONLY_SEEMS_OVER_30"' 引用的名字也可以用在 Django 的其他支持的数据库后端;但是,除了 Oracle,引用没有任何效果。
ForeignKey (othermodel,on_delete,**options) 有两个必选的参数 : 第一个参数:关联的表格(主表),在默认的情况下,外键储存的是主表的主键(Primary key)。上面的例子里,关联到 Coding 表格,默认情况下储存 Coding 表格的主键 gender。下面我们会说到,可以使用 to_field 更改 ...
ManyToManyField(verbose_name='粉丝们', to='UserInfo', through='UserFans', through_fields=('user', 'follower')) def __str__(self): return self.username class UserFans(models.Model): """ 互粉关系表 """ nid = models.AutoField(primary_key=True) user = models.ForeignKey(verbose_name='...
class Car(models.Model): Manufacturer = models.ForeignKey(Manufacturer) name = models.CharField(max_length=30) 1. 2. 3. 4. 5. 6. 该关系,用sql语句来表示,就是: CREATE TABLE `model_test_manufacturer` ( `id` integer AUTO_INCREMENT NOT NULL PRIMARY KEY, ...
I am writing a site on Django. I am making a search system using django-elasticsearch-dsl. And I have a problem when I need to index an ImageField field in the BookDocument class in order to display a book image on the book search page Here is my Book model: books/models.py class...
foreign key: 表与表之间的某种约束关系,由于这种关系的存在能够让表与表之间的数据更加完整,关联性更强; 1.1 在创建表时就对表的某些字段(与另一张表的主键相关联的字段)进行外键约束设置; table person2( id int not null auto_increment primary key, ...
Django and Postgre: psycopg2.errors.UniqueViolation: could not create unique index "main_customuser_pkey" DETAIL: Key (token)=(Key) is duplicated Posted on 2022年8月2日 at 12:22 byStack OverflowRSS this error show up when i migrate to db using python manage.py migrate, model: class Custo...