python – 由于错误的原因,Django 1.8应用程序因初始迁移而神秘失败：150“外键约束错误形成”

weixin_38077401 2019-09-12 11:53:45

我正在使用python 3.4在django 1.8中编写应用程序,我遇到了使用MySQL作为数据库后端的问题,这让我完全陷入困境. 当我开始使用新数据库并调用./manage.py migrate(或syncdb)并尝试创建初始数据库时,我得到以下回溯： (virtualenv)~/projects/projmoj (master ✘)✹✭ ᐅ ./manage.py migrate Operations to perform: Synchronize unmigrated apps: allauth, rest_framework, registration, rest_auth, projmoj, messages, project, staticfiles Apply all migrations: contenttypes, sites, sessions, task, auth, admin, authtoken, static_precompiler, account Synchronizing apps without migrations: Creating tables... Creating table project_project Creating table project_membership Running deferred SQL... Traceback (most recent call last): File "/home/tobbe/projects/projmoj/virtualenv/lib/python3.4/site-packages/django/db/backends/utils.py", line 62, in execute return self.cursor.execute(sql) File "/home/tobbe/projects/projmoj/virtualenv/lib/python3.4/site-packages/django/db/backends/mysql/base.py", line 124, in execute return self.cursor.execute(query, args) File "/home/tobbe/projects/projmoj/virtualenv/lib/python3.4/site-packages/MySQLdb/cursors.py", line 220, in execute self.errorhandler(self, exc, value) File "/home/tobbe/projects/projmoj/virtualenv/lib/python3.4/site-packages/MySQLdb/connections.py", line 36, in defaulterrorhandler raise errorvalue File "/home/tobbe/projects/projmoj/virtualenv/lib/python3.4/site-packages/MySQLdb/cursors.py", line 209, in execute r = self._query(query) File "/home/tobbe/projects/projmoj/virtualenv/lib/python3.4/site-packages/MySQLdb/cursors.py", line 371, in _query rowcount = self._do_query(q) File "/home/tobbe/projects/projmoj/virtualenv/lib/python3.4/site-packages/MySQLdb/cursors.py", line 335, in _do_query db.query(q) File "/home/tobbe/projects/projmoj/virtualenv/lib/python3.4/site-packages/MySQLdb/connections.py", line 280, in query _mysql.connection.query(self, query) _mysql_exceptions.OperationalError: (1005, 'Can\'t create table `tasks`.`#sql-1c32_9` (errno: 150 "Foreign key constraint is incorrectly formed")') 当我在Web托管服务上执行相同操作时会发生此错误,但是它可以在托管服务和localhost上使用sqlite. 我没有迁移,这些是我的模型： class Project(models.Model): name = models.CharField(max_length = 32) description = models.TextField(null=True, blank=True) creation_date = models.DateTimeField(auto_now_add=True) def get_owner(self): return self.members.filter(status=OWNER).first().user def get_membership(self, user): return self.members.filter(user=user).first() def __str__(self): return str(self.name) + " - by " + str(self.get_owner().username) class Membership(models.Model): user = models.ForeignKey(User, related_name='joined_projects') project = models.ForeignKey(Project, related_name='members') status = models.PositiveSmallIntegerField(choices=MEMBER_STATUS) join_date = models.DateTimeField(auto_now_add=True) def __str__(self): return str(self.user.username) class Sprint(models.Model): name = models.CharField(max_length = 32, null=True, blank=True) start_date = models.DateTimeField() due_date = models.DateTimeField(null=True, blank=True) project = models.ForeignKey(Project, related_name='sprints') status = models.PositiveSmallIntegerField(choices=SPRINT_STATUS, default=PLANNING) def __str__(self): return str(self.name) + " - " + str(self.project) class Category(models.Model): name = models.CharField(max_length = 32) project = models.ForeignKey(Project, related_name='categories') def __str__(self): return str(self.name) + " - " + str(self.project) class Goal(models.Model): name = models.CharField(max_length = 32) description = models.TextField(null=True, blank=True) project = models.ForeignKey(Project, related_name='goals') completion = models.PositiveSmallIntegerField(choices=COMPLETION, default=NOT_COMPLETED) def __str__(self): return str(self.name) + " - " + str(self.project) class Task(models.Model): name = models.CharField(max_length = 64) description = models.TextField(null=True, blank=True) project = models.ForeignKey(Project, related_name='tasks') category = models.ForeignKey(Category, related_name='tasks', null=True, blank=True) goal = models.ForeignKey(Goal, related_name='tasks', null=True, blank=True) creation_date = models.DateTimeField(auto_now_add=True) sprint = models.ForeignKey(Sprint, related_name='tasks', null=True, blank=True) status = models.PositiveSmallIntegerField(choices=TASK_STATUS, default=WAITING) dedicated_hours = models.DecimalField(max_digits=6, decimal_places=2, null=True, blank=True) assigned_worker = models.ForeignKey(User, null=True, blank=True) priority = models.PositiveSmallIntegerField(choices=PRIORITY, default=NORMAL) def __str__(self): return str(self.name) + " - " + str(self.project) class HourReport(models.Model): task = models.ForeignKey(Task, related_name='hour_reports') worker = models.ForeignKey(User, related_name='hour_reports') hours_spent = models.DecimalField(max_digits=6, decimal_places=2) date = models.DateTimeField(auto_now_add=True) def __str__(self): return str(self.hours_spent) + " on " + str(self.task) 我的数据库设置： DATABASES = { 'default': { 'ENGINE': 'django.db.backends.mysql', 'NAME': 'tasks', 'USER': 'root', 'PASSWORD': 'mysqlmysql', 'HOST': 'localhost', } } 版本等： > Django 1.8> Python 3.4>默认存储引擎：InnoDB> Mysqlclient 1.3.6>服务器：Amazon RDS上的MySQL 5.5.42(在虚拟主机上)>服务器：10.0.21-MariaDB-log MariaDB服务器(localhost) 当谷歌搜索时,似乎这个错误通常是人们填写他们的手动SQL代码,但我通过django自动完成. 有任何想法吗？

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