use [BNComplex1]
/****** Сценарий для команды SelectTopNRows среды SSMS  ******/
declare @t table (Describtion nvarchar(64),devnum varchar(15),BillingDayDate datetime,msgwithGPS int,MsgWithoutGPS int )
insert into @t
SELECT ad.Describtion
       ,d.DevNum
       ,bd.BillingDayDate
       ,msgwithGPS
       ,MsgWithoutGPS
        
   FROM [dbo].[BillingData] as BD
   inner join dbo.Devices as D on d.DeviceID=bd.[DeviceID]
   inner join dbo.AreaDescr as AD on AD.AreaID=bd.AreaID
   --group by ad.Describtion,d.DevNum,CONVERT (datetime,[bd.BillingDayDate],102)
   select * from @t
   select Describtion,devnum, CONVERT(varchar(7),BillingDayDate,102) as mes,SUM(msgwithGPS) msgwithGPS  
   ,SUM(MsgWithoutGPS) MsgWithoutGPS
   from @t
   group by Describtion,devnum,CONVERT(varchar(7),BillingDayDate,102)
   order by Describtion,devnum,CONVERT(varchar(7),BillingDayDate,102)