update a
set value=(select top 1 value from tablename where date>a.date and value is not null order by date)
from tablename a
where a.value is null
set value=(select top 1 value from tablename where date>a.date and value is not null order by date)
from tablename a
where a.value is null
'2003-03-10' then [date]>='2003-03-11' and [date]<'2003-03-24'then '2003-03-24' end)