Since you are trying to UPDATE a record, the error is telling you there is a field of type location_id that is mandatory and is not set. The field is shop_id.

There is no Shop defined for you to sell products from, or it isn't getting set when you create an RFQ.

To set one:

1) Make sure Manage multiple shops is checked under Settings --> Configuration --> Sales in the Quotations and Sales Orders section.

2) Refresh the User Interface in the web client by refreshing the page in your browse, or clicking in the bottom half of the company logo in the top left corner of the page.

3) Make sure there is a shop set for your company under Sales --> Configuration --> Shop

The shop dropdown is now added to the RFQ and Sales Order forms, so you can make sure one is selected before confirming,

By the way, this problem indicates an incorrect configuration somewhere during the setup of your database.

Ray.

Well, I am stuck with the tutorial until I solve this problem. Just in case, this is the stacktrace:

2013-09-01 20:34:39,706 2840 ERROR testing openerp.sql_db: bad query: insert into "stock_move" (id,"product_uos_qty","date_expected","product_uom","price_unit","product_uos","move_dest_id","product_qty","date","partner_id","product_id","name","auto_validate","location_id","company_id","priority","state","location_dest_id","purchase_line_id","picking_id",create_uid,create_date,write_uid,write_date) values (10,'10.000','2013-08-31 16:00:00',1,'56.00',1,NULL,'10.000','2013-08-31 16:00:00',6,2,'Titanium Alloy Radiator','False',NULL,1,'1','draft',12,1,10,1,(now() at time zone 'UTC'),1,(now() at time zone 'UTC'))
Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.7/openerp/sql_db.py", line 226, in execute
    res = self._obj.execute(query, params)
IntegrityError: null value in column "location_id" violates not-null constraint

2013-09-01 20:34:39,733 2840 ERROR testing openerp.tools.safe_eval: Cannot eval u'action_picking_create()'
Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.7/openerp/tools/safe_eval.py", line 241, in safe_eval
    return eval(test_expr(expr, _SAFE_OPCODES, mode=mode), globals_dict, locals_dict)
  File "", line 1, in <module>
  File "/usr/lib/pymodules/python2.7/openerp/osv/orm.py", line 374, in function_proxy
    return attr(self._cr, self._uid, [self._id], *args, **kwargs)
  File "/usr/lib/pymodules/python2.7/openerp/addons/purchase/purchase.py", line 699, in action_picking_create
    picking_ids.extend(self._create_pickings(cr, uid, order, order.order_line, None, context=context))
  File "/usr/lib/pymodules/python2.7/openerp/addons/purchase/purchase.py", line 687, in _create_pickings
    move = stock_move.create(cr, uid, self._prepare_order_line_move(cr, uid, order, order_line, picking_id, context=context))
  File "/usr/lib/pymodules/python2.7/openerp/osv/orm.py", line 4436, in create
    cr.execute('insert into "'+self._table+'" (id'+upd0+") values ("+str(id_new)+upd1+')', tuple(upd2))
  File "/usr/lib/pymodules/python2.7/openerp/sql_db.py", line 161, in wrapper
    return f(self, *args, **kwargs)
  File "/usr/lib/pymodules/python2.7/openerp/sql_db.py", line 226, in execute
    res = self._obj.execute(query, params)
IntegrityError: null value in column "location_id" violates not-null constraint

2013-09-01 20:34:39,774 2840 ERROR testing openerp.netsvc: Integrity Error
The operation cannot be completed, probably due to the following:
- deletion: you may be trying to delete a record while other records still reference it
- creation/update: a mandatory field is not correctly set

[object with reference: location_id - location.id]
Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.7/openerp/netsvc.py", line 292, in dispatch_rpc
    result = ExportService.getService(service_name).dispatch(method, params)
  File "/usr/lib/pymodules/python2.7/openerp/service/web_services.py", line 626, in dispatch
    res = fn(db, uid, *params)
  File "/usr/lib/pymodules/python2.7/openerp/osv/osv.py", line 172, in wrapper
    netsvc.abort_response(1, _('Integrity Error'), 'warning', msg)
  File "/usr/lib/pymodules/python2.7/openerp/netsvc.py", line 71, in abort_response
    raise openerp.osv.osv.except_osv(description, details)
except_osv: ('Integrity Error', 'The operation cannot be completed, probably due to the following:\n- deletion: you may be trying to delete a record while other records still reference it\n- creation/update: a mandatory field is not correctly set\n\n[object with reference: location_id - location.id]')
2013-09-01 20:34:39,826 2840 INFO testing werkzeug: 127.0.0.1 - - [01/Sep/2013 20:34:39] "POST /web/dataset/exec_workflow HTTP/1.1" 200 -

Any help will be appreciated. Thanks!