Django/PostgreSQL manage.py 刷新错误。查看'django-admin sqlflush'的输出

Question

构建：Heroku Python server，Postgresql 10.4，Django 2，wagtail 2.1

我正在尝试在 Heroku 上销毁和重新创建我的应用程序数据库。以下是我遵循的步骤：

1. 创建数据库转储(成功(
2. RM 所有迁移并重新创建"初始"迁移(成功(
3. 运行"heroku pg：重置数据库"(成功(
4. 推送新迁移和数据库转储(成功(
5. 运行 'Heroku Run Python manage.py Migrate' (成功(
6. 运行"Heroku Run Python manage.py Flush"(**失败**(

JVsquad$ heroku run python manage.py flush
Running python manage.py flush on ⬢ my_app... up, run.2459 (Hobby)
You have requested a flush of the database.
This will IRREVERSIBLY DESTROY all data currently in the 'my_app_db' database,
and return each table to an empty state.
Are you sure you want to do this?
Type 'yes' to continue, or 'no' to cancel: yes
CommandError: Database my_app_db couldn't be flushed. Possible 
reasons:
* The database isn't running or isn't configured correctly.
* At least one of the expected database tables doesn't exist.
* The SQL was invalid.
Hint: Look at the output of 'django-admin sqlflush'. That's the SQL this command wasn't able to run.

我的第 7 步本来是heroku run python manage.py loaddata db_dump.json但它也失败了，因为冲洗不起作用。

请帮忙

Answer 1

如果没有任何效果，则可以从 heroku GUI 中删除数据库并预配新的数据库。 这将解决您的直接问题。

此外，此线程建议了一个解决方案

https://github.com/wagtail/wagtail/issues/1824

Answer 2

从Mysql迁移到PostgresQL后，我遇到了同样的问题。

TRUNCATE tablename CASCADE的问题是我无法在刷新方法(即在每个测试用例方法之后运行(中设置allow_cascade=True

我覆盖了测试中使用的 Transaction 类：APITransactionTestCase

class PostgresTestCase(APITransactionTestCase):
"""
Override APITransactionTestCase class so the TRUNCATE table_name CASCADE is enabled
"""
def _fixture_teardown(self):
# Allow TRUNCATE ... CASCADE and dont emit the post_migrate signal
# when flushing only a subset of the apps
for db_name in self._databases_names(include_mirrors=False):
# Flush the database
inhibit_post_migrate = (
self.available_apps is not None or
(  # Inhibit the post_migrate signal when using serialized
# rollback to avoid trying to recreate the serialized data.
self.serialized_rollback and
hasattr(connections[db_name], '_test_serialized_contents')
)
)
call_command('flush', verbosity=3, interactive=False,
database=db_name, reset_sequences=False,
allow_cascade=True,
inhibit_post_migrate=True)

现在刷新在 Postgres 中也有效。