I'm using SQLAlchemy 0.4.6 with Python 2.5.2, and having a problem
with deleting object. Below is the testing code that shows my problem:
from sqlalchemy import *
from sqlalchemy.orm import *
engine = create_engine('sqlite:///C:/test_db.sqlite')
Session = sessionmaker(bind=engine, autoflush=True,
transactional=True)
metadata = MetaData()
class Foo(object):
def __init__(self, name):
self.name = name
foo_table = Table('foo', metadata,
Column('id', Integer, primary_key=True),
Column('name', String(40))
)
if __name__ == '__main__':
# Create database, map database table to its model
metadata.create_all(engine)
mapper(Foo, foo_table)
# Create a new Foo object, then save it to the database
db_session = Session()
f = Foo('001')
db_session.save(f)
db_session.commit()
# Try deleting Foo object created above with a new, different
session
db_session2 = Session()
f1 = db_session2.get(Foo, f.id)
print 'f =', f
print 'f1 =', f1
print 'f1 is f =', f1 is f
db_session2.delete(f)
I got a traceback below:
f = <__main__.Foo object at 0x00E64FD0>
f1 = <__main__.Foo object at 0x00E6D8D0>
f1 is f = False
Traceback (most recent call last):
File "test_sqlalchemy.py", line 39, in <module>
db_session2.delete(f)
File "C:\Python25\lib\site-packages\SQLAlchemy-0.4.6-py2.5.egg
\sqlalchemy\orm\
session.py", line 954, in delete
self._delete_impl(instance)
File "C:\Python25\lib\site-packages\SQLAlchemy-0.4.6-py2.5.egg
\sqlalchemy\orm\
session.py", line 1123, in _delete_impl
raise exceptions.InvalidRequestError("Instance '%s' is with key %s
already p
ersisted with a different identity" %
(mapperutil.instance_str(instance), instan
ce._instance_key))
sqlalchemy.exceptions.InvalidRequestError: Instance '[EMAIL PROTECTED]' is
with key (
<class '__main__.Foo'>, (1,), None) already persisted with a different
identity
It seems that when I get the object back from db with a different
session, new instance of the same db record is created in this
session. There are 2 different objects presenting the same record in
2 different sessions, and SQLAlchemy is not aware of this.
Any help or idea is appreciated!!!
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"sqlalchemy" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to [EMAIL PROTECTED]
For more options, visit this group at
http://groups.google.com/group/sqlalchemy?hl=en
-~----------~----~----~----~------~----~------~--~---
