Declare @ClientServicecode as varchar(5000)
	
  set @ClientServicecode =   select  Client_Code  + '_' +  REPLICATE('0',4-LEN(RTRIM(Service_Type_Code))) + RTRIM(Service_Type_Code) as ClientServiceCode
                       from  JobTable
 
exec  @ClientServicecode
 
getting issue while framing a dynamic query of above.