Question

我在现有表中添加了UUIDField，如下所示（由Postgres 9.4支持）：

class MyTable(TimeStampedModel):
    """ """
    ...

    uid = models.UUIDField(default=uuid.uuid4, unique=True,
                editable=False, 
                help_text="Unique identifier")                     
    class Meta:
        app_label = "core"
        db_table = "my_table"
        ordering = ['-created']

当我运行迁移时，我看到以下错误，我认为这是不可能的：

  File "/Users/josephmisiti//projects/xxx/lib/python2.7/site-packages/django/db/backends/base/schema.py", line 398, in add_field
    self.execute(sql, params)
  File "/Users/josephmisiti/projects/xxx/lib/python2.7/site-packages/django/db/backends/base/schema.py", line 111, in execute
    cursor.execute(sql, params)
  File "/Users/josephmisiti/projects/xxx/lib/python2.7/site-packages/django/db/backends/utils.py", line 79, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File "/Users/josephmisiti/projects/xxx/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/Users/josephmisiti/projects/xxx/lib/python2.7/site-packages/django/db/utils.py", line 98, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File "/Users/josephmisiti/projects/xxx/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
django.db.utils.IntegrityError: could not create unique index "additional_properties_uid_key"
DETAIL:  Key (uid)=(c0ca7e2a-87de-42d2-b188-14821a0e207a) is duplicated.

我的印象是UUID是独一无二的，这种情况永远不会发生 - 有人可以解释为什么不是这种情况！（另外，我以前见过这个）

Answer 1

我带来的解决方案是覆盖save方法：

def save(self, *args, **kwargs): if not self.uid: self.uid = uuid.uuid4() super(Model, self).save(*args, **kwargs)

Django UUID字段抛出IntegrityError

1 个答案: