The following code raises a FlushError because the child object named Cheshire is an orphan and the delete-orphan cascade rule is in effect. It seems to me that an orphan which has no database identity should be detached from its session, just as it was attached when appended to a parent's list of children. Why does SA raise an exception instead?
from sqlalchemy import * import sys meta = BoundMetaData(sys.argv[1]) parentTable = Table("tether_parents", meta, Column("id", Integer, Sequence("seq_tether_parents"), primary_key = True), Column("name", String(10), nullable = False)) childTable = Table("tether_children", meta, Column("id", Integer, Sequence("seq_tether_children"), primary_key = True), Column("parent_id", Integer, ForeignKey("tether_parents.id"), nullable = False), Column("name", String(10), nullable = False)) class Child(object): def __init__(self, name): self.name = name def __repr__(self): return "Child(%s)" % repr(self.name) class Parent(object): def __init__(self, name): self.name = name children = [] def __repr__(self): return "Parent(%s)" % repr(self.name) mapper(Child, childTable) mapper(Parent, parentTable, properties = dict(children = relation(Child,cascade="all,delete-orphan"))) meta.drop_all() meta.create_all() meta.engine.echo = False sess = create_session() p = Parent("Carroll") p.children = [Child("Alice"), Child("Dee"), Child("Dum")] sess.save(p) sess.flush() sess.close() sess = create_session(echo_uow = True) p = sess.query(Parent).get_by_name("Carroll") # New child. p.children.append(Child("Cheshire")) # Oops, changed my mind. del p.children[3] sess.flush() sess.close() --~--~---------~--~----~------------~-------~--~----~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~----------~----~----~----~------~----~------~--~---