Django的：从Postgres数据库导入数据时无法适应错误

Question

我在使用从转储的数据安装夹具奇怪的错误。我使用psycopg2，和django1.1.1

silver:probsbox oleg$ python manage.py loaddata /Users/oleg/probs.json 
Installing json fixture '/Users/oleg/probs' from '/Users/oleg/probs'.
Problem installing fixture '/Users/oleg/probs.json': Traceback (most recent call last):
  File "/opt/local/lib/python2.5/site-packages/django/core/management/commands/loaddata.py", line 153, in handle
    obj.save()
  File "/opt/local/lib/python2.5/site-packages/django/core/serializers/base.py", line 163, in save
    models.Model.save_base(self.object, raw=True)
  File "/opt/local/lib/python2.5/site-packages/django/db/models/base.py", line 495, in save_base
    result = manager._insert(values, return_id=update_pk)
  File "/opt/local/lib/python2.5/site-packages/django/db/models/manager.py", line 177, in _insert
    return insert_query(self.model, values, **kwargs)
  File "/opt/local/lib/python2.5/site-packages/django/db/models/query.py", line 1087, in insert_query
    return query.execute_sql(return_id)
  File "/opt/local/lib/python2.5/site-packages/django/db/models/sql/subqueries.py", line 320, in execute_sql
    cursor = super(InsertQuery, self).execute_sql(None)
  File "/opt/local/lib/python2.5/site-packages/django/db/models/sql/query.py", line 2369, in execute_sql
    cursor.execute(sql, params)
  File "/opt/local/lib/python2.5/site-packages/django/db/backends/util.py", line 19, in execute
    return self.cursor.execute(sql, params)
ProgrammingError: can't adapt

首先我检查互联网上类似的问题。这一个似乎非常有关： http://code.djangoproject.com/ticket/5996，作为我的数据具有许多非ASCII符号

但实际上我已经检查了我的Django的安装和它的确定有

莫非你的建议是什么错误

====

由第一个答案建议添加打印语句后继续调查。日志看起来是这样的：

silver:probsbox oleg$ python manage.py loaddata /Users/oleg/probs.json 
Installing json fixture '/Users/oleg/probs' from '/Users/oleg/probs'.
<DeserializedObject: Novice>
<DeserializedObject: Junior>
<DeserializedObject: Chess enthusiast>
<DeserializedObject: Experienced player >
<DeserializedObject: Smart player>
Problem installing fixture '/Users/oleg/probs.json': Traceback (most recent call last):
  File "/opt/local/lib/python2.5/site-packages/django/core/management/commands/loaddata.py", line 153, in handle
    print obj
  File "/opt/local/lib/python2.5/site-packages/django/core/serializers/base.py", line 155, in __repr__
    return "<DeserializedObject: %s>" % smart_str(self.object)
  File "/opt/local/lib/python2.5/site-packages/django/utils/encoding.py", line 107, in smart_str
    return str(s)
  File "/opt/local/lib/python2.5/site-packages/django/db/models/base.py", line 335, in __str__
    return force_unicode(self).encode('utf-8')
  File "/opt/local/lib/python2.5/site-packages/django/utils/encoding.py", line 71, in force_unicode
    s = unicode(s)
  File "/Users/oleg/Sites/probsbox/registration/models.py", line 58, in __unicode__
    return u"%s's profile" %(self.user.username)
  File "/opt/local/lib/python2.5/site-packages/django/db/models/fields/related.py", line 257, in __get__
    rel_obj = QuerySet(self.field.rel.to).get(**params)
  File "/opt/local/lib/python2.5/site-packages/django/db/models/query.py", line 305, in get
    % self.model._meta.object_name)
DoesNotExist: User matching query does not exist.

silver:probsbox oleg$ 

这最后评论错误

<DeserializedObject: qwert2000's profile>

问题安装夹具“/Users/oleg/probs.json”：回溯（最近最后调用）：   文件“/opt/local/lib/python2.5/site-packages/django/core/management/commands/loaddata.py”，线路154，在手柄     obj.save（）   文件“/opt/local/lib/python2.5/site-packages/django/core/serializers/base.py”，线路163，在保存     models.Model.save_base（self.object，生=真）   文件 “/opt/local/lib/python2.5/site-packages/django/db/models/base.py”，线路495，在save_base     导致= manager._insert（值，return_id = update_pk）   文件 “/opt/local/lib/python2.5/site-packages/django/db/models/manager.py”，线路177，在_insert     返回insert_query（self.model，价值观，** kwargs）   文件 “/opt/local/lib/python2.5/site-packages/django/db/models/query.py”，线1087，在insert_query     返回query.execute_sql（return_id）   文件 “/opt/local/lib/python2.5/site-packages/django/db/models/sql/subqueries.py”，线320，在execute_sql     光标=超级（InsertQuery，自我）.execute_sql（无）   文件 “/opt/local/lib/python2.5/site-packages/django/db/models/sql/query.py”，线2369，在execute_sql     cursor.execute（SQL，则params）   文件“/opt/local/lib/python2.5/site-packages/django/db/backends/util.py” 19行，在执行     返回self.cursor.execute（SQL，则params） ProgrammingError：无法适应

Answer 1

好吧，我最终从我的数据库复制转储，并在本地恢复它没有巨蟒...

Answer 2

在can't adapt错误是由psycopg2当它接收到的数据类型，它不知道如何转化为SQL语句中的值上升。例如，如果你不小心通过列表，比如，对于被认为是一个整数的值，psycopg2将提高这无法适应错误。

在faq.txt文件附带psycopg2的源分布这样解释：

  

为什么!cursor.execute()引发异常的无法适应的？

     

Psycopg Python对象在SQL字符串表示通过查找转换       在的对象类。唯一的例外是当你试图通过上调       作为查询参数的对象，其没有用于注册适配器       它的类。参见：参考：adapting-new-types用于信息

<击>可能是你最好第一通在发现有问题的值是在充分详细模式运行loaddata：蟒manage.py loaddata --verbosity = 2 /Users/oleg/probs.json

好了，我希望loaddata冗长会工作，我也不会承认，我从来没有发现调试适应错误Django的loaddata的一种优雅的方式。在过去，我已经诉诸了Django的loaddata功能将打印报表，这样我可以看到，当发生错误的值被反序列化。我已经编辑django/core/management/loaddata.py。在obj.save()功能看handle()的。我希望这表白激励别人共享一个更好的解决方案： - ）