Пример
declare @date datetime
select @date = getdate()
declare @table table (FromDate datetime, ToDate datetime, mesg varchar(50))
insert @table values('2008','12-31-2010', 'once')
insert @table values('01-01-2011','12-31-2011', 'this year')
insert @table values('01-01-2012','12-31-2015', 'future')
select mesg from @table where @date between FromDate and ToDate