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我想知道你是否可以在继承的模型中拥有独一无二的 slug？

我有三个模型，一个基础和两个扩展它。

该基地具有AutoSlugField从现场生成的独特性name。

蛞蝓在BaseModel但是如果我保存 aHamster和 anElderberry两者都具有相同的名称，那么我会得到一个IntegrityError.

显然，这是因为唯一性不是在基本级别而是在子类级别强制执行的。有没有人对此有很好的解决方案？

BaseModel不是abstract并且需要保持这种状态，因为我正在使用“django-model-utils” InheritanceManager。

设置

Django==1.4.3
django-extensions==1.0.2
django-autoslug==1.6.1

模型.py

class BaseModel(models.Model):
    name = models.CharField(max_length=255)
    slug = AutoSlugField(populate_from='name', unique=True, db_index=True)
    # ... other fields

    objects = InheritanceManager()

class HamsterModel(BaseModel):
    useful_info = models.CharField(max_length=128)
    # ... other fields

class ElderberryModel(BaseModel):
    pointless_info = models.CharField(max_length=128)
    # ... other fields

安慰

>>> h = HamsterModel()
>>> h.name = 'One'
>>> h.save()
>>> h.slug
u'one'
>>> e = ElderberryModel()
>>> e.name = 'One'
>>> e.save()
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "/home/blah/.envs/vfaces/local/lib/python2.7/site-packages/django/db/models/base.py", line 463, in save

    self.save_base(using=using, force_insert=force_insert, force_update=force_update)
  File "/home/blah/.envs/blah/local/lib/python2.7/site-packages/django/db/models/base.py", line 506, in save
_base
    self.save_base(cls=parent, origin=org, using=using)
  File "/home/blah/.envs/blah/local/lib/python2.7/site-packages/django/db/models/base.py", line 551, in save
_base
    result = manager._insert([self], fields=fields, return_id=update_pk, using=using, raw=raw)
  File "/home/blah/.envs/blah/local/lib/python2.7/site-packages/django/db/models/manager.py", line 203, in _
insert
    return insert_query(self.model, objs, fields, **kwargs)
  File "/home/blah/.envs/blah/local/lib/python2.7/site-packages/django/db/models/query.py", line 1593, in in
sert_query
    return query.get_compiler(using=using).execute_sql(return_id)
  File "/home/blah/.envs/blah/local/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 912,
 in execute_sql
    cursor.execute(sql, params)
  File "/home/blah/.envs/blah/local/lib/python2.7/site-packages/django/db/backends/util.py", line 40, in exe
cute
    return self.cursor.execute(sql, params)
  File "/home/blah/.envs/blah/local/lib/python2.7/site-packages/django/db/backends/mysql/base.py", line 114,
 in execute
    return self.cursor.execute(query, args)
  File "/home/blah/.envs/vfaces/local/lib/python2.7/site-packages/MySQLdb/cursors.py", line 201, in execute
    self.errorhandler(self, exc, value)
  File "/home/blah/.envs/blah/local/lib/python2.7/site-packages/MySQLdb/connections.py", line 36, in default
errorhandler
    raise errorclass, errorvalue
IntegrityError: (1062, "Duplicate entry 'one' for key 'slug'")
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2 回答 2

1

好的，所以在挖掘了源代码之后，发现文档自从我上次查看以来已经更新。

因此，如果您添加objects = models.Manager()到您的BaseModel并将其传递给AutoSlugField. 这将检查蛞蝓BaseModel而不是子类。

class BaseModel(models.Model):
    objects = models.Manager()
    name = models.CharField(max_length=255)
    slug = AutoSlugField(populate_from='name', unique=True, db_index=True, managers=objects)
    # ... other fields
于 2013-01-22T16:03:35.633 回答
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In database you have only one slug field in BaseModel table, HamsterModel and ElderberryModel are connected to BaseModel using foreign key. The only way I see in this situation is remove unique=True and check uniqueness at model level in save method.

于 2013-01-22T14:58:58.010 回答