sql server - python sqlalchemy - can't get cascade delete to work - in mssql manager -

i have code, thats been taken sqlalchemy site

class order(base):     __tablename__ = 'order'     id = column(integer, sequence('tri_id_seq'), primary_key=true)     text = column(string(1024), nullable=false)     items = relationship("item", cascade="save-update, delete-orphan, merge, delete", backref="parent")  class item(base):     __tablename__ = 'item'     id = column(integer, sequence('tri_id_seq'), primary_key=true)     text = column(string(1024), nullable=false)     parent_id = column(integer, foreignkey('order.id')) 

i want deletes order cascade down , delete items well. in code:

# test insert/delete - save data mssql server i1 = item(text="item one") i2 = item(text="item two") o = order(text="one", items=[i1, i2]) session.add(o) session.commit()  session.delete(o) # delete # tests make sure items/order gone .... session.commit() 

this works ok.

but if try , delete order in ms sql management studio. i.e.

delete [dbo].[order] id = 1 

i error "the delete statement conflicted reference constraint fk__item__parent_id_1d00044f" conflict error blah blah....

i guess theres missing on relationship definitions can't see it.

any help/thoughts?

ta.

class comment(base):     __tablename__ = 'comments'      id = column(integer, primary_key=true)     user_id = column(integer, foreignkey("users.id", ondelete='cascade'), nullable=false)      user = relationship("user", backref=backref('comments', cascade="all,delete", order_by=id)) 

this kind of setup works me, user class doesn't have special fields except primary key. basically, works intended, when delete user - comments gone well. doesn't have deletion through sqlalchemy either, code creates appropriate table structure, if delete user manually (sql query) - cascade deletion still work.