Expected Singleton Error After Adding Many2many Field to Search Condition

Question

I'm getting an expected singleton error after adding a many2many field in my search_count condition.

The structure consists of 3 classes, job, location, and employee. What I'm trying to do is to get the number of employees of each job at each location.

This works as expected with a many2many widget in xml:

(String parameters were excluded)

class job(models.Model):
  _inherit               = 'hr.job'

  rel_locations          = fields.Many2many(comodel_name='hr.locations')

  num_location_employees = fields.Integer(compute='_set_location_employees')

  def _set_location_employees(self):
     for rec in self:
        rec.num_location_employees = self.env['hr.employee'].search_count([('locations', '=', 3)])

It gives me a list of jobs with the number of employees in location with id 3.

However, after changing the id of 3 to

('locations', '=', rec.rel_locations.id)

I get

Expected singleton: hr.locations(3,4)

Here is the essential locations class

class locations(models.Model):
  _name          = 'hr.locations'

  employee       = fields.One2many(comodel_name='hr.employee', inverse_name='locations')
  rel_jobs       = fields.Many2many(comodel_name='hr.job')

  name           = fields.Char(...)

I'm still pretty new to this and any help would be appreciated. Thanks in advance.

Answer 1

You can only use the dot notation (.) to access a single record and you have multiple ones there. Check the documentation on the part that says field access

Trying to read or write a field on multiple records will raise an error.

The rec.rel_locations is an ORM one2many that contains 2 records to hr.locations model. You have first get the id of each of those records and then create your domain like this:

('locations', 'in', [rel_location_id1,rel_location_id2])

For more information check the documentation part I have posted and also:

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