from odoo import models, fields class SaleOrder(models.Model): _inherit = 'sale.order' woo_bind_ids = fields.One2many('woo.order', 'sale_order_id', string='WooCommerce Orders') woo_order_count = fields.Integer(compute='_compute_woo_order_count', string='WC Orders') def _compute_woo_order_count(self): for order in self: order.woo_order_count = len(order.woo_bind_ids)