custom aggregated column does not work with nullable=False

[omer9564]

I have two ORM models:

1. Component
2. Inventory

There is a one to many relationship between Component to Inventory

Component has a custom aggregated column named quantity defined as

@aggregated(
        "inventories", mapped_column(Integer, nullable=False, server_default="0")
    )
    def quantity(self) -> Mapped[int]:
        return func.sum(Inventory.quantity)

I have a component with id component-1 and 2 inventories with id inventory-1 and inventory-2
when I delete both of them, the package generates the following query:

UPDATE components SET quantity=(SELECT sum(inventories.quantity) AS sum_1
                                         FROM inventories
                                         WHERE components.id = inventories.component_id), updated_at=now() WHERE components.id IN ('component-1')

This query results on trying to set null in the quantity column because there are no inventories that match the where clause

Couldn't find anything in the documentation regarding this or open issue about this issue.

Using:

• python 3.10
• SQLAlchemy 2
• sqlalchemy-utils 0.41.1