Tefnet Developers wrote: > > Hi, > > and here comes another problem with my project utilizing SQLAlchemy :). > > I am trying to use ORM in AttributeExtension: > (http://dpaste.com/109454/) > ========================================================= > import sqlalchemy > import sqlalchemy.ext.declarative > > Base = sqlalchemy.ext.declarative.declarative_base(mapper = > sqlalchemy.orm.mapper) > > engine = sqlalchemy.create_engine('sqlite:///:memory:', echo = False) > > session = sqlalchemy.orm.scoped_session(sqlalchemy.orm.sessionmaker(bind > = engine)) > > Base.metadata.bind = engine > > class AttrEx(sqlalchemy.orm.interfaces.AttributeExtension): > def set(self, state, value, oldvalue, initiator): > for o in session.query(Foo): > pass > return value > > class Foo(Base): > Id = sqlalchemy.Column( sqlalchemy.types.Integer, primary_key = > True, autoincrement =True) > __tablename__ = 'foo' > > class Bar(Base): > Id = sqlalchemy.Column(sqlalchemy.types.Integer, primary_key=True, > autoincrement = True) > someAttr = > sqlalchemy.orm.column_property(sqlalchemy.Column(sqlalchemy.types.Integer), > extension = AttrEx()) > __tablename__ = 'bar' > > Base.metadata.create_all() > > a = Bar() > session.add(a) > a.someAttr = 5 > assert a.someAttr == 5 > session.commit() > assert a.someAttr == 5 > ========================================================= > > Seccond assert explodes. It seems that query'ing in AttrEx's set() > method triggers flush (autoflush which I need) and somehow value > returned by set() gets lost. Is there a correct way to manipulate other > mapped objects in AttributeExtensions?
you can disable the autoflush if you say query.autoflush(False).whatever(). I'd start there. At the same time the AttributeExtensions are firing off in the middle of a sensitive section so some issues are unavoidable. --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
