declare @datos table (iddevice int null, SerialNumber varchar(100) null, Estado varchar(50) null, Factura varchar(30)) insert into @datos select id_device, SerialNumber, click_TipoEstado.Name,null from tabla_Devices inner join tabla_TiposEstado on tabla_Devices.FK_id_DeviceEstado = tabla_TiposEstado.id_Estado update @datos set Factura = InvoiceNumber from Facturas where fk_id_device = iddevice and YEAR(invoicedate) = 2011 and MONTH(invoicedate) = 5 select Estado, COUNT(Estado) as Cuantos, COUNT(Factura) as Facturados from @datos group by Estado select * from @datos where Estado = 'Funcionando' and Factura is null