【发布时间】：2011-03-06 00:37:27
【问题描述】：
我很少在将模型实例添加到 many2many 字段时遇到这样的异常，即：
some_instance_A.my_m2m.add(some_instance_B)).
它可以说是 99/100 次。对我来说看起来很奇怪的是破折号 - 因为主键是整数..
模型字段定义如下：
my_m2m = ManyToManyField(B)
所以这是最简单的 M2M 定义
完整的追溯（为保护隐私进行了少量修改:)）：
File "*******", line 278, in process_request
some_instance_A.my_m2m.add(some_instance_B)
File "/var/lib/python-support/python2.5/django/db/models/fields/related.py", line 490, in add
self._add_items(self.source_field_name, self.target_field_name, *objs)
File "/var/lib/python-support/python2.5/django/db/models/fields/related.py", line 574, in _add_items
'%s_id' % target_field_name: obj_id,
File "/var/lib/python-support/python2.5/django/db/models/query.py", line 352, in create
obj.save(force_insert=True, using=self.db)
File "/var/lib/python-support/python2.5/django/db/models/base.py", line 435, in save
self.save_base(using=using, force_insert=force_insert, force_update=force_update)
File "/var/lib/python-support/python2.5/django/db/models/base.py", line 528, in save_base
result = manager._insert(values, return_id=update_pk, using=using)
File "/var/lib/python-support/python2.5/django/db/models/manager.py", line 195, in _insert
return insert_query(self.model, values, **kwargs)
File "/var/lib/python-support/python2.5/django/db/models/query.py", line 1479, in insert_query
return query.get_compiler(using=using).execute_sql(return_id)
File "/var/lib/python-support/python2.5/django/db/models/sql/compiler.py", line 783, in execute_sql
cursor = super(SQLInsertCompiler, self).execute_sql(None)
File "/var/lib/python-support/python2.5/django/db/models/sql/compiler.py", line 727, in execute_sql
cursor.execute(sql, params)
File "/var/lib/python-support/python2.5/django/db/backends/mysql/base.py", line 86, in execute
return self.cursor.execute(query, args)
File "/var/lib/python-support/python2.5/MySQLdb/cursors.py", line 166, in execute
self.errorhandler(self, exc, value)
File "/var/lib/python-support/python2.5/MySQLdb/connections.py", line 35, in defaulterrorhandler
raise errorclass, errorvalue
IntegrityError: (1062, "Duplicate entry '1830327-1792993' for key 'some_instance_A_id'")
【问题讨论】：
-
我遇到了同样的（非常烦人的）问题，但我还没有找到解决方案：stackoverflow.com/questions/19303866/…。你有运气吗？
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@rsp 我切换到 Postgresql 并开始享受生活:)
标签： django orm django-models