ondelete='cascade' constraint not generated in postgres

[Ferdinand]

class dimu_settlement_portal_all(osv.osv):
    _inherit = "dimu.settlement_portal_all"

....
{ 'csv_file_id' : fields.many2one
             ('holophon.csv_files','CSV file', select=True, required=True, readonly=True, ondelete='cascade'),

the constraint is not generated in postgres.

we had some problems, because the filed was NULL initially, but even after fixing it the constraint is not generated during update of the module.

[Anup(SerpentCS) (anup-serpent)]

Hello Dr Ferdinand, Experts,

   We need to discuss more on this. Would you please share your views?

Thanks.

[Jay Vora (Serpent Consulting Services) (jayvora)]

I guess readonly=True and ondelete='cascade' create a conflict.

[Patrick Amstutz (patrick-amstutz)]

Same problem here :

'sale_order_id': fields.many2one('sale.order', 'Sale Order', on_delete='cascade', readonly=True),

constraints are not generated. This is a serious problem and should not be listed as 'wishlist'.

[Juan Márquez (jmarquez)]

I have the same problem, and a new one: some primary key are not generated