Вот мой код:
from sqlalchemy import create_engine, Column, Integer
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker
database_url = 'mysql://some_path'
engine = create_engine(database_url)
Base = declarative_base(engine)
class Users(Base):
__tablename__ = 'Users'
__table_args__ = {'autoload':True}
metadata = Base.metadata
Session = sessionmaker(bind=engine)
session = Session()
Он работает, но ...
Можно ли привязать движок, когда я хочу, не только при импорте время? Так что я могу обернуть эту реализацию в класс.
На данный момент я получаю
class Users(Base):
File "/usr/lib/python2.5/site-packages/SQLAlchemy-0.6.5-py2.5.egg/sqlalchemy/ext/declarative.py", line 1231, in __init__
_as_declarative(cls, classname, cls.__dict__)
File "/usr/lib/python2.5/site-packages/SQLAlchemy-0.6.5-py2.5.egg/sqlalchemy/ext/declarative.py", line 1122, in _as_declarative
**table_kw)
File "/usr/lib/python2.5/site-packages/SQLAlchemy-0.6.5-py2.5.egg/sqlalchemy/schema.py", line 209, in __new__
table._init(name, metadata, *args, **kw)
File "/usr/lib/python2.5/site-packages/SQLAlchemy-0.6.5-py2.5.egg/sqlalchemy/schema.py", line 260, in _init
msg="No engine is bound to this Table's MetaData. "
File "/usr/lib/python2.5/site-packages/SQLAlchemy-0.6.5-py2.5.egg/sqlalchemy/schema.py", line 2598, in _bind_or_error
raise exc.UnboundExecutionError(msg)
sqlalchemy.exc.UnboundExecutionError: No engine is bound to this Table's MetaData. Pass an engine to the Table via autoload_with=<someengine>, or associate the MetaData with an engine via metadata.bind=<someengine>
, когда движок не указан: Base = declarative_base ()