我开发了一个Django应用程序，部署在DigitalOcean的Ubuntu服务器上，使用Postgres db。一切正常，没有任何问题，但今天添加新模型后，我得到了这个错误：relation "documents_app_document" does not exist虽然我有这个模型，其中一些模型继承自Document模型。但不知何故，它被从数据库中删除，现在我不能在迁移后将其添加回数据库。我如何将该模型作为表再次添加到数据库？
p.s：但是我已经打开了名为'0001_initial.py'的迁移文件，有migrations.CreateModel( name='Document'...models.py：
class Document(models.Model):
created_date = models.DateTimeField(default=timezone.now, blank=True, null=True)
added_by = CurrentUserField()
purpose = models.CharField(blank=True, max_length=300, null=True)
def __str__(self):
return str(self.added_by)
class MedicalDocument(Document):
policy_number = models.CharField(max_length=20, blank=True, null=True)
medical_institution = models.CharField(max_length=100, blank=True, null=True)字符串
迁移错误：
Operations to perform:
Unapply all migrations: documents_app
Running migrations:
Rendering model states... DONE
Unapplying documents_app.0001_initial...Traceback (most recent call last):
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/backends/utils.py", line 84, in _execute
return self.cursor.execute(sql, params)
psycopg2.errors.UndefinedTable: relation "documents_app_document" does not exist
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "manage.py", line 22, in <module>
main()
File "manage.py", line 18, in main
execute_from_command_line(sys.argv)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/core/management/__init__.py", line 381, in execute_from_command_line
utility.execute()
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/core/management/__init__.py", line 375, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/core/management/base.py", line 323, in run_from_argv
self.execute(*args, **cmd_options)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/core/management/base.py", line 364, in execute
output = self.handle(*args, **options)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/core/management/base.py", line 83, in wrapped
res = handle_func(*args, **kwargs)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/core/management/commands/migrate.py", line 234, in handle
fake_initial=fake_initial,
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/migrations/executor.py", line 121, in migrate
state = self._migrate_all_backwards(plan, full_plan, fake=fake)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/migrations/executor.py", line 196, in _migrate_all_backwards
self.unapply_migration(states[migration], migration, fake=fake)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/migrations/executor.py", line 269, in unapply_migration
state = migration.unapply(state, schema_editor)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/migrations/migration.py", line 175, in unapply
operation.database_backwards(self.app_label, schema_editor, from_state, to_state)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/migrations/operations/fields.py", line 120, in database_backwards
schema_editor.remove_field(from_model, from_model._meta.get_field(self.name))
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/backends/base/schema.py", line 487, in remove_field
self.execute(sql)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/backends/base/schema.py", line 137, in execute
cursor.execute(sql, params)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/backends/utils.py", line 99, in execute
return super().execute(sql, params)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/backends/utils.py", line 67, in execute
return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/backends/utils.py", line 76, in _execute_with_wrappers
return executor(sql, params, many, context)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/backends/utils.py", line 84, in _execute
return self.cursor.execute(sql, params)
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/utils.py", line 89, in __exit__
raise dj_exc_value.with_traceback(traceback) from exc_value
File "/home/azersigorta/insuranceproject/env/lib/python3.5/site-packages/django/db/backends/utils.py", line 84, in _execute
return self.cursor.execute(sql, params)
django.db.utils.ProgrammingError: relation "documents_app_document" does not exist型
3条答案
按热度按时间isr3a4wc1#
在添加/更改/添加新模型之后，始终确保运行
python manage.py makemigrations和python manage.py migrate。（迁移树重新排列，数据库失败等）出了问题，你可以通过执行python manage.py migrate {app_name} {migration_index}来返回到特定的迁移。所以我建议你尝试python manage.py migrate {app_name} zero，然后重新迁移回最新版本。您可能还需要使用--fake。mgdq6dx12#
以下是一个可能的解决方法：删除旧的迁移。注解掉所有模型中与
Document模型相关的所有字段，并执行makemigrations和migrate以单独创建“文档”表。取消注解其他模型中与Document相关的字段，然后重新进行迁移。rdrgkggo3#
我遇到了（看起来）同样的问题。无法运行迁移或任何东西.
我的理由是：
我有2个数据库（带DB路由器）。在一个 db2 模型中，我使用一个函数来生成选项，该函数使用数据库1的模型X中的数据。我在创建数据库1.模型X后编写了该函数。
当我现在尝试在没有新的Database-1.Model-X的生产系统上部署新的迁移时，我得到了相同的错误。
我看到了三种可能性：
也许这对有同样或类似问题的人来说是一个启发。
问候
卡尔