log in as guest/guest
On May 19, 2009, at 11:52 AM, klaus wrote:
>
> How do I get the privileges for that?
>
>
> On 19 Mai, 17:33, Michael Bayer <mike...@zzzcomputing.com> wrote:
>> it seems like a small bug and you can file a ticket for that, but
>> the
>> intent is that you'd be using None to represent NULL in the general
>> case.
>>
>> On May 19, 2009, at 11:21 AM, klaus wrote:
>>
>>
>>
>>> Hi!
>>
>>> Here is a small (and not very useful) example to demonstrate the
>>> problem. A table "user" contains a reference to itself (so that I
>>> don't need a second table). This foreign key translates to a
>>> relation.
>>> When I compare the corresponding attribute to null(), I get a
>>> traceback. It all works if I compare it to None instead.
>>
>>> from sqlalchemy.engine import create_engine
>>> from sqlalchemy.schema import MetaData, Table, Column, ForeignKey
>>> from sqlalchemy.types import Integer
>>> from sqlalchemy.orm import mapper, relation, create_session
>>> from sqlalchemy.sql import null
>>
>>> engine = create_engine("postgres://...")
>>> metadata = MetaData(engine)
>>
>>> user = Table("user", metadata,
>>> Column("id", Integer, nullable=False, primary_key=True),
>>> Column("fk", Integer, ForeignKey("public.user.id")),
>>> schema="public", useexisting=True, autoload=False)
>>
>>> class User(object):
>>> pass
>>
>>> mapper(User, user, properties={"ref": relation(User,
>>> uselist=False)})
>>
>>> metadata.create_all()
>>
>>> session = create_session()
>>
>>> print session.query(User).filter(User.ref == null()).all()
>>
>>> metadata.drop_all()
>>
>>> (The last line is not executed.)
>>
>>> Here's the traceback:
>>
>>> Traceback (most recent call last):
>>> File "sqlatest.py", line 24, in ?
>>> print session.query(User).filter(User.ref == null()).all()
>>> File "/home/barthelmannk/PortaleHeadZope/sandbox/eggs/
>>> SQLAlchemy-0.5.4p1-py2.4.egg/sqlalchemy/sql/expression.py", line
>>> 1253,
>>> in __eq__
>>> return self.operate(operators.eq, other)
>>> File "/home/barthelmannk/PortaleHeadZope/sandbox/eggs/
>>> SQLAlchemy-0.5.4p1-py2.4.egg/sqlalchemy/orm/attributes.py", line
>>> 120,
>>> in operate
>>> return op(self.comparator, *other, **kwargs)
>>> File "/home/barthelmannk/PortaleHeadZope/sandbox/eggs/
>>> SQLAlchemy-0.5.4p1-py2.4.egg/sqlalchemy/orm/properties.py", line
>>> 492,
>>> in __eq__
>>> return _orm_annotate(self.property._optimized_compare(other,
>>> adapt_source=self.adapter))
>>> File "/home/barthelmannk/PortaleHeadZope/sandbox/eggs/
>>> SQLAlchemy-0.5.4p1-py2.4.egg/sqlalchemy/orm/properties.py", line
>>> 623,
>>> in _optimized_compare
>>> value = attributes.instance_state(value)
>>> AttributeError: '_Null' object has no attribute '_sa_instance_state'
>>
>>> Cheers
>>> Klaus
> >
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"sqlalchemy" group.
To post to this group, send email to sqlalchemy@googlegroups.com
To unsubscribe from this group, send email to
sqlalchemy+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/sqlalchemy?hl=en
-~----------~----~----~----~------~----~------~--~---
