Mastering Odoo 18 Command Class: The Modern Way to Handle Relations

If you've been developing in Odoo for a while, you've likely memorized the "magic tuples" like (0, 0, vals) or (6, 0, ids). While functional, these numerical codes are cryptic, prone to errors, and hard for new developers to understand.

Enter the Command class. Introduced in later versions and now the standard in Odoo 18, it provides a readable, Pythonic interface for managing One2Many and Many2Many relationships. This tutorial will guide you through replacing those old tuples with clean, expressive code.

line_ids = [(0, 0, {
    'product_id': 10, 
    'qty': 5
})]

line_ids = [
    Command.create({
        'product_id': 10, 
        'qty': 5
    })
]

What is the Command Class?

The Command class is a namespace that contains static methods corresponding to the 7 relational operations supported by Odoo. Instead of remembering that 0 means "create" and 2 means "delete", you simply call Command.create() or Command.delete().

from odoo import Command

# Now you can use Command.create(), Command.update(), etc.

The 6 Essential Commands

Let's look at real-world examples using a Sales Order context, where we manage order_line (One2many) and tag_ids (Many2many).

1. Create New Records

Replaces (0, 0, values). Creates a new record in the co-model and links it.

# Create a new sale order line
order.write({
    'order_line': [
        Command.create({
            'product_id': product_id,
            'product_uom_qty': 5,
            'price_unit': 150.00
        })
    ]
})

2. Update Existing Records

Replaces (1, id, values). Updates fields on an existing linked record.

# Update the price of line with ID 10
order.write({
    'order_line': [
        Command.update(10, {'price_unit': 200.00})
    ]
})

3. Delete Records Permanently

Replaces (2, id, 0). Removes the link AND deletes the record from the database. Use carefully!

# Delete the line completely
order.write({
    'order_line': [
        Command.delete(11)
    ]
})

4. Link Existing Records (Many2Many)

Replaces (4, id, 0). Adds a relationship to an existing record.

user.write({
    'category_id': [
        Command.link(14)  # 14 is the ID of the tag
    ]
})

5. Unlink Records (Remove Relation)

Replaces (3, id, 0). Removes the link but keeps the record in the database. Common for Many2Many.

user.write({
    'category_id': [
        Command.unlink(14)
    ]
})

6. Clear All Records

Replaces (5, 0, 0). Removes all links from the field. For One2many, this deletes the records; for Many2many, it just unlinks them.

order.write({
    'order_line': [
        Command.clear()
    ]
})

7. Set Specific List (Replace All)

Replaces (6, 0, [ids]). Replaces the current list of linked IDs with a new one.

user.write({
    'category_id': [
        Command.set([1, 2, 3])
    ]
})

Frequently Asked Questions