id,summary,reporter,owner,description,type,status,component,version,severity,resolution,keywords,cc,stage,has_patch,needs_docs,needs_tests,needs_better_patch,easy,ui_ux 10454,IntegrityError while deleting object with complex constraint,liangent,nobody,"i have models like this (the whole project is too complex and i dont want to put it here): {{{ class P(Model): pass class TC(Model): p = ForeignKey(P) class S(Model): p = ForeignKey(P) class CR(Model): s = ForeignKey(S) tc = ForeignKey(TC) # note: s.p always equals to tc.p }}} when i'm trying to delect a P object (with all its TC, S, CR sub-objects existing), an IntegrityError occurs, saying {{{ Cannot delete or update a parent row: a foreign key constraint fails (`proj/m_tc`, CONSTRAINT `p_id_refs_id_16cb2ff4a6a127c1` FOREIGN KEY (`p_id`) REFERENCES `main_p` (`id`))') }}}. {{{ Environment: Request Method: POST Request URL: http://example.com/admin/m/p/2/delete/ Django Version: 1.1 pre-alpha Python Version: 2.5.2 Installed Applications: ['django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.sites', 'django.contrib.admin', 'django.contrib.admindocs', 'django.contrib.redirects', 'django.contrib.comments', 'django.contrib.flatpages', 'notification', 'avatar', 'tagging', 'announcements', 'registration', 'proj.cm', 'proj.m', 'proj.u', 'proj.mk'] Installed Middleware: ('django.middleware.locale.LocaleMiddleware', 'django.middleware.common.CommonMiddleware', 'django.contrib.redirects.middleware.RedirectFallbackMiddleware', 'django.contrib.flatpages.middleware.FlatpageFallbackMiddleware', 'django.contrib.csrf.middleware.CsrfMiddleware', 'django.contrib.sessions.middleware.SessionMiddleware', 'django.middleware.transaction.TransactionMiddleware', 'django.contrib.auth.middleware.AuthenticationMiddleware', 'proj.middleware.CAM', 'django.middleware.doc.XViewMiddleware') Traceback: File ""/usr/lib/python2.5/site-packages/django/core/handlers/base.py"" in get_response 86. response = callback(request, *callback_args, **callback_kwargs) File ""/usr/lib/python2.5/site-packages/django/contrib/admin/sites.py"" in root 450. return self.model_page(request, *url.split('/', 2)) File ""/usr/lib/python2.5/site-packages/django/views/decorators/cache.py"" in _wrapped_view_func 44. response = view_func(request, *args, **kwargs) File ""/usr/lib/python2.5/site-packages/django/contrib/admin/sites.py"" in model_page 469. return admin_obj(request, rest_of_url) File ""/usr/lib/python2.5/site-packages/django/contrib/admin/options.py"" in __call__ 799. return self.delete_view(request, unquote(url[:-7])) File ""/usr/lib/python2.5/site-packages/django/contrib/admin/options.py"" in delete_view 722. obj.delete() File ""/usr/lib/python2.5/site-packages/django/db/models/base.py"" in delete 464. delete_objects(seen_objs) File ""/usr/lib/python2.5/site-packages/django/db/models/query.py"" in delete_objects 1014. del_query.delete_batch(pk_list) File ""/usr/lib/python2.5/site-packages/django/db/models/sql/subqueries.py"" in delete_batch 88. self.do_query(self.model._meta.db_table, where) File ""/usr/lib/python2.5/site-packages/django/db/models/sql/subqueries.py"" in do_query 35. self.execute_sql(None) File ""/usr/lib/python2.5/site-packages/django/db/models/sql/query.py"" in execute_sql 1996. cursor.execute(sql, params) File ""/usr/lib/python2.5/site-packages/django/db/backends/util.py"" in execute 19. return self.cursor.execute(sql, params) File ""/usr/lib/python2.5/site-packages/django/db/backends/mysql/base.py"" in execute 83. return self.cursor.execute(query, args) File ""/var/lib/python-support/python2.5/MySQLdb/cursors.py"" in execute 166. self.errorhandler(self, exc, value) File ""/var/lib/python-support/python2.5/MySQLdb/connections.py"" in defaulterrorhandler 35. raise errorclass, errorvalue Exception Type: IntegrityError at /admin/m/p/2/delete/ Exception Value: (1451, 'Cannot delete or update a parent row: a foreign key constraint fails (`proj/m_tc`, CONSTRAINT `p_id_refs_id_16cb2ff4a6a127c1` FOREIGN KEY (`p_id`) REFERENCES `m_p` (`id`))') }}}",,closed,"Database layer (models, ORM)",dev,,duplicate,,,Unreviewed,0,0,0,0,0,0