Finally, the field is not transfered because there is an attribute on field product_uom: attrs="{'readonly': [('state', 'in', ('purchase', 'done', 'cancel'))]}"

Because the status of pruchase order is "purchase", the field is readonly and not in values during the insert. Why this field is readonly?

Thanks

This is a wild guess but in Odoo any readonly field will not be stored in the database. So what I think happens here is that in your view when you choose a product, the product_uom field is properly set by the onchange event but since it's readonly it will be only visual. In that case you need to make your product_uom field as non-readonly.

It would be nice to see which version of odoo you have to help you more.

Hi,

In the error message itself, there is the hint about the issue.  In the sale.order.line and in the purchase.order.line the product_uom field is a required field.

As you haven't supplied the value for the field in your Insert query you are getting the issue. So update the query by providing the product_uom.

Also, check and make sure that no other required fields are missed

Thanks