Odoo 12 Development Essentials - Fourth Edition

One-to-many inverse relationships

A one-to-many relationship is the inverse of the many-to-one.  It lists the records of the related Model that have a reference to this record.

For example, in the library book model, the publisher_id field is a many-to-one relationship with the partner model. This means that the partner model can have a one-to-many inverse relation with the book model, listing the books published by each partner.

To have that relationship available, we can add it in the partner model. Add the library_app/models/res_partner.py file with this:

from odoo import fields, modelsclass Partner(models.Model):
    _inherit = 'res.partner'
    published_book_ids = fields.One2many(
        'library.book',  # related model
 'publisher_id', # field ...