postgresql – 如何在Odoo 8中创建One2one关系？

我无法合并这两组数据,因为：

>特定记录可能仅出现在集合A中,仅出现在集合B中,或者既出现在集合A中,也出现在集合B中;和
>集合A和集合B中的记录之间的关联是暂时的,这意味着记录可以变得相关联并且可以变得不相关;和
>集合A中的数据处理方式与集合B中的数据不同;和
>存在外部架构限制.

当集合A中的记录与集合B中的记录相关联时,我想链接这两个记录.链接记录时,关系必须是一对一的.我如何保证这种关系是一对一的关系？

以下代码似乎很接近,但我不熟悉使用Odoo并且不确定如何分析这种方法是否保证一对一的关系.

import openerp

class A(openerp.models.Model):

  _name = 'set.a'

  _sql_constraints = [
    ('set_b_id','unique("set_b_id")','Field set_b_id must be unique.'),]

  # Constrained to be unique (see SQL above) which essentially changes
  # this end of the Many2one relationship to a One2one relationship. (The
  # other end of the relationship must also be constrained.)

  set_b_id = openerp.fields.Many2one(
    comodel_name='set.b',)

class B(openerp.models.Model):

  _name = 'set.b'

  # Constrained to tie with either zero keys or one key (see function
  # below) which essentially changes this end of the One2many
  # relationship to a One2one relationship. (The other end of the
  # relationship must also be constrained.)

  set_a_id = openerp.fields.One2many(
    comodel_name='set.a',inverse_name='set_b_id',)

  @openerp.api.constrains('set_a_id')
  def _constrains_set_a_id(self):
    if len(self.set_a_id) > 1:
        raise openerp.exceptions.ValidationError('Additional linkage failed.')

另一种方法可能是扩展openerp.fields以重新创建以前弃用的One2one关系,但我不确定是否可以干净地完成.