declare @t table (a int, b int, c int, d int);
insert into @t
values
 (1, 2, 3, 4), (5, 6, null, 7);

select
 *
from
 @t t
where
 not exists(
  select
   1
  from
   (select t.* for xml raw, elements xsinil, type) a(x)
  where
   a.x.exist('declare namespace xsi = "http://www.w3.org/2001/XMLSchema-instance"; /row/*[@xsi:nil = "true"]') = 1
 );