Related Attribute in Odoo

There may be times when customizing in Odoo that we need to immediately display a field from a related model in another model. Odoo’s related attribute makes it simple for us to accomplish that.

The `related` attribute in Odoo is used to create a field in one model that is directly linked to a field in another model. This means that the field’s value is automatically fetched from the related model, without the need for manual updates.

Here’s a simple example where we are going to add a field name phone_number in the sale order form view after the field partner_id

sale_order.py

from odoo import api,models,fields


class SaleOrder(models.Model):
    _inherit = "sale.order"

    phone_number=fields.Char(string="Phone",related="partner_id.phone")

views.xml

<?xml version="1.0" encoding="utf-8" ?>
<odoo>
    <record id="view_order_form_inherit_phone" model="ir.ui.view">
        <field name="name">sale.order.form.inherit.phone</field>
        <field name="model">sale.order</field>
        <field name="inherit_id" ref="sale.view_order_form"/>
        <field name="arch" type="xml">
            <xpath expr="//field[@name='partner_id']" position="after">
                <field name="phone_number"/>
            </xpath>
        </field>
    </record>
</odoo>

In this example:

– `phone_number`: This is the new field we are creating in the `sale. order` model.

– `related=’partner_id.phone’`: This indicates that the value of the field phone_number should be fetched from the phone field of via the field partner_id (which is a many2one relationship to the `res. partner` model).

From the Screenshot, it’s quite clear that when selecting the customer the phone_number field gets automatically updated with the corresponding phone number of the customer.

Here when the Customer is ‘My Company’ the phone_number gets updated to 123456789, Similarly when the Customer is Administrator the phone number  automatically fetches the value 12345

–Readonly by Default: Fields with the `related` attribute are readonly by default because their values are derived from another model.

The `related` attribute in Odoo is an also efficient way to link fields across models, enabling you to access and display related data effortlessly.