我正在为购物车制作一个Order型号的购物车，我需要创建一个在下订单时自动递增的字段:
class Order(models.Model):
cart = models.ForeignKey(Cart)
add_date = models.DateTimeField(auto_now_add=True)
order_number = models.IntegerField()
enable = models.BooleanField(default=True)
我怎样才能实现IntegerField自动递增呢？
在Django
1 : Django model class has default field with name id which is auto increment Field.
2 : You can define your own auto increment field using AutoField
field.
class Order(models.Model):
auto_increment_id = models.AutoField(primary_key=True)
# primary_key = True if you do not want to use default field "id" given by django to your model
+------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Table | Create Table | +------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------+ | core_order | CREATE TABLE `core_order` ( `auto_increment_id` int(11) NOT NULL AUTO_INCREMENT, PRIMARY KEY (`auto_increment_id`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 | +------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------+ 1 row in set (0.01 sec)
class Order(models.Model):
add_date = models.DateTimeField(auto_now_add=True)
+-------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Table | Create Table | +-------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+ | core_order | CREATE TABLE `core_order` ( `id` int(11) NOT NULL AUTO_INCREMENT, `add_date` datetime NOT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 | +-------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------+