Django ignore_conflicts 不适用于用户模型答案

【问题标题】：Django ignore_conflicts doesn't work for User modelDjango ignore_conflicts 不适用于用户模型
【发布时间】：2020-02-12 08:25:32
【问题描述】：

我正在尝试创建大量用户来测试我的 Django 应用程序。我已经在其他模型上使用过这种方法并且它有效，但在这里它没有。执行时，它会显示以下错误。使用了最新的 Django 版本（2.2.6）。 The documentation states:

(...) 将 ignore_conflicts 参数设置为 True 会告诉数据库忽略插入任何违反约束（例如重复唯一值）的行的失败。

我的代码：

def draftUser(i):
    return User(username='Testguy' + str(i), first_name=randomString(7), last_name=randomString(5))

user_cache = []

for i in range(1, 10000):
    user_cache(draftUser(i))

User.objects.bulk_create(user_cache, ignore_conflicts=True)

完整的错误回溯：

Traceback (most recent call last):
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/query.py", line 538, in get_or_create
    return self.get(**kwargs), False
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/query.py", line 408, in get
    self.model._meta.object_name
django.contrib.auth.models.DoesNotExist: User matching query does not exist.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/backends/sqlite3/base.py", line 383, in execute
    return Database.Cursor.execute(self, query, params)
sqlite3.IntegrityError: UNIQUE constraint failed: auth_user.username

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "PROJECT_PATH/src/populate.py", line 261, in <module>
    olaf, created = User.objects.get_or_create(username='Olaf', first_name='Olaf', last_name='Dude')
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/manager.py", line 82, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/query.py", line 541, in get_or_create
    return self._create_object_from_params(kwargs, params)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/query.py", line 583, in _create_object_from_params
    raise e
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/query.py", line 575, in _create_object_from_params
    obj = self.create(**params)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/query.py", line 422, in create
    obj.save(force_insert=True, using=self.db)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/contrib/auth/base_user.py", line 66, in save
    super().save(*args, **kwargs)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/base.py", line 741, in save
    force_update=force_update, update_fields=update_fields)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/base.py", line 779, in save_base
    force_update, using, update_fields,
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/base.py", line 870, in _save_table
    result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/base.py", line 908, in _do_insert
    using=using, raw=raw)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/manager.py", line 82, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/query.py", line 1186, in _insert
    return query.get_compiler(using=using).execute_sql(return_id)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/models/sql/compiler.py", line 1335, in execute_sql
    cursor.execute(sql, params)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/backends/utils.py", line 99, in execute
    return super().execute(sql, params)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/backends/utils.py", line 67, in execute
    return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/backends/utils.py", line 76, in _execute_with_wrappers
    return executor(sql, params, many, context)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/utils.py", line 89, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/Users/USERNAME/PROJECT_PATH/env/lib/python3.7/site-packages/django/db/backends/sqlite3/base.py", line 383, in execute
    return Database.Cursor.execute(self, query, params)
django.db.utils.IntegrityError: UNIQUE constraint failed: auth_user.username

【问题讨论】：

这可能是auth_user 的问题 - 听起来您正在使用安全包，而数据库可能允许忽略安全包可能不允许的约束？
据我所知，我不使用安全包...但是我在单独的类中使用一对一字段来管理有关用户的其他信息，这可能是问题？它们不会被创建，因为它们的钩子不是由 bulk_create 触发的。
我不知道 - 但查看错误似乎与 auth_user 周围的约束特别相关。
那我真的不知道哪里错了……
您使用的是什么数据库？此功能 doesn't work 适用于 PostgreSQL

标签： python django

【解决方案1】：

非常抱歉，社区无法解决这个问题，因为我的代码示例没有显示实际的错误行。我更改了问题中提供的行，并在下面的代码中添加了名字和姓氏，但认为这不会有什么不同，因为脚本之前已经正常运行了。

这是导致错误的行：

dude, created = User.objects.get_or_create(username='testguy', first_name='Testguy', last_name='Testguy')

抛出异常是因为数据库中已经存在用户名为“testguy”的用户，但他没有相同的数据。所以 'get_or_create' 既不能获取用户也不能创建它。

我的解决方案是删除数据库中的用户并重新运行脚本。

【讨论】：