How to create a model in Odoo without a table in the database

There are cases when is needed to have a model that will not be represented by a table in the database. By default, Odoo creates a table for every Model​ and ​TransientModel​,  but, there is option to change that by setting up the attribute ​_auto​ to False​  

For example, If we want to create a new model PartnerContact​ that will have the base fields and methods for our PartnerCompany​ and ​PartnerPerson​ models the base definition of the model should look like: 

from odoo import models
 
class PartnerContact(models.Model):
    _name = 'partner.contact'
    _description = 'Partner Contact'
    _auto = False        

Another way of doing this is by inheriting the class AbstractModel​ which by default has the attribute ​_auto​ set to ​False​​

from odoo import models

class PartnerContact(models.AbstractModel):
    _name = 'partner.contact'
    _description = 'Partner Contact'