How selecting from product.product table only single item for creating simple warehouse-renting module? Also, How possible that selected choice somehow fill product name, price, barcode field for example is created by myself. Moreover I deal with this error 

Error: 
Odoo Server Error 

Traceback (most recent call last): 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\http.py", line 653, in _handle_exception 
return super(JsonRequest, self)._handle_exception(exception) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\http.py", line 312, in _handle_exception 
raise pycompat.reraise(type(exception), exception, sys.exc_info()[2]) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\tools\pycompat.py", line 87, in reraise 
raise value 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\http.py", line 695, in dispatch 
result = self._call_function(**self.params) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\http.py", line 344, in _call_function 
return checked_call(self.db, *args, **kwargs) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\service\model.py", line 97, in wrapper 
return f(dbname, *args, **kwargs) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\http.py", line 337, in checked_call 
result = self.endpoint(*a, **kw) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\http.py", line 939, in __call__ 
return self.method(*args, **kw) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\http.py", line 517, in response_wrap 
response = f(*args, **kw) 
File "c:\program files (x86)\odoo 11\odoo\addons\web\controllers\main.py", line 938, in call_button 
action = self._call_kw(model, method, args, {}) 
File "c:\program files (x86)\odoo 11\odoo\addons\web\controllers\main.py", line 926, in _call_kw 
return call_kw(request.env[model], method, args, kwargs) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\api.py", line 689, in call_kw 
return call_kw_multi(method, model, args, kwargs) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\api.py", line 680, in call_kw_multi 
result = method(recs, *args, **kwargs) 
File "<decorator-gen-48>", line 2, in button_immediate_upgrade 
File "c:\program files (x86)\odoo 11\odoo\odoo\addons\base\module\module.py", line 72, in check_and_log 
return method(self, *args, **kwargs) 
File "c:\program files (x86)\odoo 11\odoo\odoo\addons\base\module\module.py", line 613, in button_immediate_upgrade 
return self._button_immediate_function(type(self).button_upgrade) 
File "c:\program files (x86)\odoo 11\odoo\odoo\addons\base\module\module.py", line 552, in _button_immediate_function 
modules.registry.Registry.new(self._cr.dbname, update_module=True) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\modules\registry.py", line 85, in new 
odoo.modules.load_modules(registry._db, force_demo, status, update_module) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\modules\loading.py", line 376, in load_modules 
force, status, report, loaded_modules, update_module, models_to_check) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\modules\loading.py", line 274, in load_marked_modules 
perform_checks=perform_checks, models_to_check=models_to_check 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\modules\loading.py", line 153, in load_module_graph 
registry.init_models(cr, model_names, {'module': package.name}) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\modules\registry.py", line 311, in init_models 
func() 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\fields.py", line 2442, in update_db_foreign_keys 
sql.add_foreign_key(cr, self.relation, self.column2, comodel._table, 'id', 'cascade') 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\tools\sql.py", line 150, in add_foreign_key 
cr.execute(query.format(tablename1, columnname1, tablename2, columnname2, ondelete)) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\sql_db.py", line 155, in wrapper 
return f(self, *args, **kwargs) 
File "C:\Program Files (x86)\Odoo 11\odoo\odoo\sql_db.py", line 232, in execute 
res = self._obj.execute(query, params) 
psycopg2.ProgrammingError: relation "_unknown" does not exist

rent.py

from odoo import api, models, fieldsclass Warehouse(models.Model):    _name = 'rent.warehouse'    _inheirt = 'sales.order.line'    product_ids = fields.Many2many("product.product", ondelete="cascade", string="Produktas", required=True)    rented = fields.Selection([('rented', 'Isnuomota'),                                   ('unrented', 'Neisnomuota')                                   ], string="rented", default="unrented")​

rent.xml

<?xml version="1.0" encoding="utf-8"?>
    <odoo>



          <record id="warehouse_form_view" model="ir.ui.view">
            <field name="name">Sandėlio forma</field>

            <field name="model">rent.warehouse</field>

            <field name="arch" type="xml">

                <form string="Sandėlio forma">
                    <sheet>
                        <group>
                        <field name="product_ids"/>
                        <field name="rented" widget="selection"/>

                        </group>
                    </sheet>
                </form>

            </field>

        </record>

       <record model="ir.ui.view" id="warehouse_tree_view">
            <field name="name">warehouse.tree</field>
            <field name="model">rent.warehouse</field>
            <field name="arch" type="xml">
                <tree string="Warehouse Tree">
                    <field name="rented"/>
                </tree>
            </field>
        </record>

          <record model="ir.actions.act_window" id="sandelis_list_action">
            <field name="name">Sandėlis</field>
            <field name="res_model">rent.warehouse</field>
            <field name="view_type">form</field>
            <field name="view_mode">tree,form,search</field>
        </record>

    <menuitem id="main_sandelis_menu" name="Sandelis"/>




        <menuitem id="sandelis_menu"
            name="Sandelis"
            parent="main_sandelis_menu"
            action="sandelis_list_action"/>
    
</odoo>