create table Deals
( 
  Deals_Id int, 
  Amount float
)
go
create table DealsHist
( 
  Deals_Id int, 
  Amount float
)
go
CREATE VIEW DealsAll AS
SELECT Deals_Id, Amount FROM Deals 
UNION ALL
SELECT Deals_Id, Amount FROM DealsHist 
go


declare @Amount float, @Deal_Id int
declare @archive int, @work int

select @Amount =  100 , @Deal_Id =  1 

select @work =  1  from Deals where Deals_Id = @Deal_Id
select @archive =  1  from DealsHist where Deals_Id = @Deal_Id

select @work as _work,  @archive as _archive

select @Amount = isnull(@Amount, Amount) 
from DealsAll
where  Deals_Id = @Deal_Id

select @Amount