Override many2one with many2many

Question

I try to override many2one field with many2many

 property_product_pricelist = fields.Many2many('product.pricelist',
                                                      string="Sale Pricelist",
                                                      help="This pricelist will be used, instead of the default one, for sales to the current partner")

and i get this error when try to save values

File "/home//workspace/odoo-9.0/openerp/models.py", line 5384, in _browse
    env.prefetch[cls._name].update(ids)
TypeError: unhashable type: 'list'

also i tryid like this

property_product_pricelist = fields.Many2many('product.pricelist', column1='partner_id', column2='pricelist_id')

but get

ProgrammingError: column product_pricelist_res_partner_rel.pricelist_id does not exist

LINE 1: SELECT product_pricelist_res_partner_rel.pricelist_id, produ...

I would suggest you not to do that because if a Many2one field already exists, it must be used at many different places and you will have errors everywhere, because a singleton is expected instead of a list. You should create another field instead. — Harlan, Aug 07 '18 at 06:01
What you are doing is bad because you will break the logic.Ask you the question `why I need a many2many field ?` — Kenly, Aug 07 '18 at 13:17

score 0 · Accepted Answer · edited Aug 13 '18 at 15:45

Best solution I came up with.

create a many2many field totally new
write an onchange method which sets the value of the original field (here the many2one) to the new many2many field

multiply_pricelists_ids = fields.Many2many(
        'product.pricelist', string='Multiply Pricelists')

    @api.onchange('property_product_pricelist')
    @api.multi
    def pricelist_change(self):
        self.multiply_pricelists_ids =  self.property_product_pricelist

Override many2one with many2many

1 Answers1