Django模型字段的随机值

So I am able to generate a random id using uuid So far so good But when I try to database i get same value

所以我能够使用uuid生成一个随机id到目前为止很好但是当我尝试数据库时，我得到相同的值

 def f():
    d = uuid4()
    str = d.hex
    return str[0:16]

class Q(models.Model):
  a = models.CharField(max_length=150)
  b = models.IntegerField(max_length=25)
  c = models.IntegerField(max_length=32 , default=0)
  d = models.ManyToManyField(Ans , related_name='aa')
  e = models.CharField(max_length=18 , default = f() ,unique=True )


class Ans(models.Model):
  sub = models.CharField(max_length=150) 


-----------------------------------------------------------------

And I'm inserting like this

而我正在这样插入

def ins(request):
     t =random.randint(0, 1000)
     p = Q(a = t , b=0 , c=0)
     p.save()
     return HttpResponse('Saved')

Just curious what the hell is happening here

只是好奇这里到底发生了什么

Side note: If I set e.unique = False I get 2-3 with the same e values before I get a new UUID values

旁注：如果我设置e.unique = False，在得到新的UUID值之前，我得到2-3具有相同的e值

1 个解决方案

#1

You should not call the function that you are passing to default:

您不应该调用要传递给默认值的函数：

e = models.CharField(max_length=18, default=f, unique=True)

FYI, according to docs, you should pass a value or a callable:

根据文档，你应该传递一个值或一个可调用的值：

The default value for the field. This can be a value or a callable object. If callable it will be called every time a new object is created.

字段的默认值。这可以是值或可调用对象。如果可调用，则每次创建新对象时都会调用它。

#1