Do you need it to be an actual relationship? It's common to use an association proxy for this:
https://docs.sqlalchemy.org/en/13/orm/extensions/associationproxy.html#simplifying-association-objects Hope that helps, Simon On Fri, Mar 20, 2020 at 7:47 PM Mark Aquino <maquino1...@gmail.com> wrote: > > I'd like to create a relationship that joins a table linked to a related > table on a model: > > I have a Vessel class, a Well class, and a Batch class. > > Vessel and Well are related via a FK on Well (well.vessel_id) but Batch is a > many to many relationship with Well, e.g. > > Batch(Base): > id = Column(Integer) > > Well(Base): > id = Column(Integer) > vessel_id = Column(Integer) > batches = relationship("Batch", secondary="mix_well_tracked_entity") > > Is it possible to make a relationship on Vessel to the Batches linked to its > wells? > > Vessel(Base): > id = Column(Integer) > wells = relationship("Well") > wells_batches = relationship("Batch", ...???) > > > select * from vessel v join well w on w.vessel_id = v.id join > mix_well_tracked_entity mix1 on mix1.well_id = w.id join batch b on b.id = > mix1.tracked_entity_id; > > -- > 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 view this discussion on the web visit > https://groups.google.com/d/msgid/sqlalchemy/54af97fe-9de7-4cb2-a4d9-96b33107c6af%40googlegroups.com. -- 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 view this discussion on the web visit https://groups.google.com/d/msgid/sqlalchemy/CAFHwexc3eUFLWT0sPoqm%2B8RUM0eUKPhHq8kDiwFDPq6zBfn1Gw%40mail.gmail.com.
