Many thanks! On Wednesday, March 28, 2018 at 6:42:16 PM UTC+3, Mike Bayer wrote: > > the backrefs intentionally don't keep fanning deep into object graph > for this kind of thing, so if you want it to go one hop further you > can add an event to do that directly: > > from sqlalchemy import event > from sqlalchemy.orm import attributes > > > @event.listens_for(Address.user, "set") > def _intercept_set(target, value, oldvalue, initiator): > > if isinstance(oldvalue, User) and "address" in oldvalue.__dict__: > attributes.set_committed_value(oldvalue, "address", None) > > > the "set_committed_value" is to avoid triggering any new events which > will cause a recursion overflow. > > > > On Wed, Mar 28, 2018 at 10:49 AM, Serhii Mozghovyi <egna...@gmail.com > <javascript:>> wrote: > > Is it possible to make child objects (many-to-one side) delete itself > from > > the old parent's collection when it is added to a different parent? > > See the file attached. The old parent remains unaware that he doesn't > have > > this child anymore. > > > > P.S. session.expire() is an obvious solution but too heavy. I expect > some > > event-based collection synchronization, much like backref > (back_populates) > > connected collections. > > > > -- > > SQLAlchemy - > > The Python SQL Toolkit and Object Relational Mapper > > > > http://www.sqlalchemy.org/ > > > > To post example code, please provide an MCVE: Minimal, Complete, and > > Verifiable Example. See http://stackoverflow.com/help/mcve for a full > > description. > > --- > > You received this message because you are subscribed to the Google > Groups > > "sqlalchemy" group. > > To unsubscribe from this group and stop receiving emails from it, send > an > > email to sqlalchemy+...@googlegroups.com <javascript:>. > > To post to this group, send email to sqlal...@googlegroups.com > <javascript:>. > > Visit this group at https://groups.google.com/group/sqlalchemy. > > For more options, visit https://groups.google.com/d/optout. >
-- SQLAlchemy - The Python SQL Toolkit and Object Relational Mapper http://www.sqlalchemy.org/ To post example code, please provide an MCVE: Minimal, Complete, and Verifiable Example. See http://stackoverflow.com/help/mcve for a full description. --- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To post to this group, send email to sqlalchemy@googlegroups.com. Visit this group at https://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/d/optout.
