Odoo Development Prerequisites

Prerequisites at a Glance

Python: How Much Do You Need?

Python is the non-negotiable prerequisite. Odoo's backend is Python code from top to bottom. Here's what you need specifically:

• OOP is essential — every model is a class that inherits from models.Model. You need to understand self, class attributes, instance methods, and inheritance.
• Decorators from day one — @api.depends, @api.onchange, @api.constrains, @api.model. If you don't understand decorators, you won't understand why Odoo methods are structured the way they are.
• Exceptions — raise ValidationError("...") is the standard way to block invalid data in Odoo.
• String, datetime, dict operations — used constantly in computed field logic and data transformations.

from odoo import models, fields, api
from odoo.exceptions import ValidationError

class LibraryBook(models.Model):
    _name = 'library.book'
    _description = 'Library Book'

    name = fields.Char(required=True)
    price = fields.Float()
    discount = fields.Float()
    final_price = fields.Float(compute='_compute_final_price', store=True)

    @api.depends('price', 'discount')
    def _compute_final_price(self):
        for record in self:
            record.final_price = record.price * (1 - record.discount / 100)

    @api.constrains('price')
    def _check_price(self):
        for record in self:
            if record.price < 0:
                raise ValidationError("Price cannot be negative.")

This single example uses: class inheritance, class attributes, decorators (@api.depends, @api.constrains), a for loop over self (a recordset), instance attribute assignment, and exception raising. All of these Python concepts appear in your first module.

XML: What You Need

Odoo views, menus, actions, security records, email templates, and website pages are all written in XML. You need to understand:

• Element attributes: <field name="foo" string="Bar" required="1"/>
• Nesting and parent-child relationships
• Self-closing tags: <field name="x"/>
• Escaping: &, <, >

Odoo's XML uses a template engine called QWeb which adds directives: t-if, t-foreach, t-field, t-esc. These are used in website pages and PDF report templates. The HTML course on ylearner covers XML syntax directly — the concepts transfer to Odoo's XML without any gaps.

SQL: How Much?

You write Odoo domains (Python lists that compile to SQL WHERE clauses) — not raw SQL. A domain like [('state', '=', 'sale'), ('partner_id.country_id.code', '=', 'US')] becomes a SQL WHERE clause with a JOIN automatically.

However, understanding SQL helps you:

• Write efficient domains (understanding JOINs helps you avoid N+1 patterns)
• Debug slow queries using PostgreSQL's EXPLAIN ANALYZE
• Write advanced reports using raw SQL with self.env.cr.execute()

The SQL course on ylearner covers everything you need for Odoo development.

OWL JS: When Do You Need It?

OWL is Odoo's JavaScript UI framework. How much you need depends on what you're building:

• Backend-only modules (models, views, wizards, reports): OWL is optional — you write Python and XML only.
• Client actions, custom field widgets, dashboards: OWL is required — you write JavaScript components.
• POS screens: OWL is required — POS is an OWL single-page application.
• Portal/Website development: OWL is NOT needed — you use QWeb templates and standard JavaScript.

Quick Self-Assessment

If you can answer these questions, you're ready to start the Odoo module development section: