IntegrityError rises from test test_generic_key_deletion when it runs with the test test_generic_key_cross_database_protection for the INNODB

[rahul.priyadarshi@…]

When i ran test cases of multiple_databases model of regressiontests then "test_generic_key_deletion" test case gave Error at the point where it was trying to create Review object using "other" db, but when i ran "test_generic_key_deletion" test case only then it passed perfectly.

When i narrowed the problem and run this test case with "test_generic_key_cross_database_protection" then even it gives Error at same line.

In my investigation i found that in "test_generic_key_cross_database_protection" test case, one Reiview object is getting created and because there exist FK relationship with ContentType, content type record for this is getting populated in DB and content type lookup are cached. At the end of this test case, content type record gets cleared by rollback, but content type lookup still remain in cache, so that when inside "test_generic_key_deletion" it tries to create Review object it gets content type from the cache and does not have to go to DB. Next when it tries to populate review table, Integrity error is raised as it has not made entry to contenttype table.

$ python runtests.py --settings=settings_mysql multiple_database.QueryTestCase.test_generic_key_cross_database_protection multiple_database.QueryTestCase.test_generic_key_deletion


Creating test database for alias 'default'...
Creating test database for alias 'other'...
.E
======================================================================
ERROR: test_generic_key_deletion (regressiontests.multiple_database.tests.QueryTestCase)
Cascaded deletions of Generic Key relations issue queries on the right database
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/.../.../.../Django-1.3-rc-1/tests/regressiontests/multiple_database/tests.py", line 825, in test_generic_key_deletion
    review = Review.objects.using('other').create(source="Python Weekly", content_object=dive)
  File "/home/.../.../.../lib/python2.5/site-packages/django/db/models/query.py", line 360, in create
    obj.save(force_insert=True, using=self.db)
  File "/home/.../.../.../lib/python2.5/site-packages/django/db/models/base.py", line 460, in save
    self.save_base(using=using, force_insert=force_insert, force_update=force_update)
  File "/home/.../.../.../lib/python2.5/site-packages/django/db/models/base.py", line 553, in save_base
    result = manager._insert(values, return_id=update_pk, using=using)
  File "/home/.../.../.../lib/python2.5/site-packages/django/db/models/manager.py", line 195, in _insert
    return insert_query(self.model, values, **kwargs)
  File "/home/.../.../.../lib/python2.5/site-packages/django/db/models/query.py", line 1436, in insert_query
    return query.get_compiler(using=using).execute_sql(return_id)
  File "/home/.../.../.../lib/python2.5/site-packages/django/db/models/sql/compiler.py", line 791, in execute_sql
    cursor = super(SQLInsertCompiler, self).execute_sql(None)
  File "/home/.../.../.../lib/python2.5/site-packages/django/db/models/sql/compiler.py", line 735, in execute_sql
    cursor.execute(sql, params)
  File "/home/.../.../.../lib/python2.5/site-packages/django/db/backends/mysql/base.py", line 86, in execute
    return self.cursor.execute(query, args)
  File "/home/.../.../.../lib/python2.5/site-packages/MySQL_python-1.2.3-py2.5-linux-x86_64.egg/MySQLdb/cursors.py", line 174, in execute
    self.errorhandler(self, exc, value)
  File "/home/.../.../.../lib/python2.5/site-packages/MySQL_python-1.2.3-py2.5-linux-x86_64.egg/MySQLdb/connections.py", line 36, in defaulterrorhandler
    raise errorclass, errorvalue
IntegrityError: (1452, 'Cannot add or update a child row: a foreign key constraint fails (`test_testpy2/multiple_database_review`, CONSTRAINT `content_type_id_refs_id_82d6f7ab` FOREIGN KEY (`content_type_id`) REFERENCES `django_content_type` (`id`))')

----------------------------------------------------------------------
Ran 2 tests in 0.040s

FAILED (errors=1)
Destroying test database for alias 'default'...
Destroying test database for alias 'other'...

I am setting storage engine through OPTIONS key of the DATABASES setting as follows:

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql', 
        'NAME': 'djangodb1',
        'USER': '****',
        'PASSWORD': '****',
        'HOST': '****',
        'PORT': '****',
        'OPTIONS': {
                'init_command': 'SET storage_engine=INNODB',
        },
    },
    'other': {
	'ENGINE': 'django.db.backends.mysql',
        'NAME': 'djangodb1', 
        'USER': '****', 
        'PASSWORD': '****',
        'HOST': '****',
        'PORT': '****',
        'OPTIONS': {
                'init_command': 'SET storage_engine=INNODB',
        },
	}
}

[Russell Keith-Magee]

I can't reproduce this with my INNODB testbed. One possible problem is that your 'other' database isn't actually an 'other' database -- it's an alias to the same database. If I reproduce that condition in my test suite, I get a test failure -- not the one you describe, but a failure nonetheless.

The report doesn't explicitly say that you've run this test with a recent checkout -- the version flag is set to 1.3rc1, but you don't reference the version in the report; it's possible that you might have seen different problems with the database setup you describe if you had an older version of Django.

[anonymous]

Due to typo setting file shows same database but actually i have run it with two different databases.

I have run it with Django-1.3-beta-1 and Django-1.3rc-1 both, but in both version of Django i got same error as specified in above report.

[rahul.priyadarshi@…]

Did you try to reproduce it with two different databases?

[Russell Keith-Magee]

Ok - reproduced; the key point is that you need to have 2 MySQL InnoDB databases. MySQL + SQLite isn't enough to reproduce the problem.

[rahul.priyadarshi@…]

Yes. In my case since i was updating the DB2 django adpater for Django 1.3, i was using 2 DB2 databases. FWIW first time we had added value to Django even before a release has been made. Hey am I am getting better at this :-)

[rahul.priyadarshi@…]

Django-1.3 have been released already, wondering when you are going to resolve this.

[Russell Keith-Magee]

Nobody has presented a patch. It's not on my personal list of criticial bugs that I want to look into (at least -- it's no higher than any other unresolved bug in Django). Based on the fact that no-one else has weighed in, I'm going to guess it isn't a high priority for anyone else, either.

So -- It will be resolved when someone provides a resolution. If this is an important bug for you, then *you* need to be the one to track down the problem.

[Aymeric Augustin]

Change UI/UX from NULL to False.

[Aymeric Augustin]

Change Easy pickings from NULL to False.

[Aymeric Augustin]

I couldn't replicate the issue. It must have been fixed at some point.

% python runtests.py --settings=test_mysql multiple_database.tests.QueryTestCase.test_generic_key_cross_database_protection multiple_database.tests.QueryTestCase.test_generic_key_deletion
Testing against Django installed in '/Users/myk/Documents/dev/django/django'
Creating test database for alias 'default'...
Creating test database for alias 'other'...
..
----------------------------------------------------------------------
Ran 2 tests in 0.051s

OK
Destroying test database for alias 'default'...
Destroying test database for alias 'other'...