On Jun 6, 2011, at 6:11 PM, Geoff wrote: > I've searched for an answer to this but can't find one but I did find > an old archived e-mail discussing this which refers to ticket #249. > > I have two tables in a many-many relationship. I do not want deletes > to cascade between these two tables but I do want any delete to > cascade to the secondary table in order to prevent the secondary table > having rows that point to nowhere. > > A recent check on my (sqlite) database shows that SQLAlchemy does not > do this automatically but the discussion I found seems to indicate > that this should happen. Is it possible that this is a regression? Or > maybe I used be doing something that I'm not?
The table referenced by "secondary=" in a relationship() is managed entirely, regardless of cascade setting, but only from the perspective of the parent. Meaning if A references a collection of B, the row in a_to_b will be deleted if you 1. delete A, or 2. remove a B from A's collection. Deleting a B by itself as in session.delete(B) won't have an effect unless you apply a backref to the relationship so that each B also knows about its collection of A. -- 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.
