On Thu, Sep 13, 2018 at 10:50 PM Alex Rothberg <agrothb...@gmail.com> wrote: > > Is it possible to hint at sqla the order in which it should write out changes > to the DB? > > I am having issues in which I add two new objects to a session, a and b where > a depends on b, but sqla is flushing a before b leading to an fk issue. I can > solve this a few ways: explicitly calling flush after adding b, or changing > the fk constraint to be initially deferred. Ideally I would not have to do > either of these. >
If you have configured a relationship between the two classes (http://docs.sqlalchemy.org/en/latest/orm/tutorial.html#building-a-relationship), and you've linked the objects together using that relationship (a.b = b), then SQLAlchemy will flush them in the correct order. If you are generating your IDs in Python and assigning them to the primary and foreign key columns directly, SQLAlchemy probably won't understand the dependency. Does using a relationship fix your problem? Simon -- 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.
