create table #t (id int,ch char,na varchar(20),flag char(1))
 
insert into #t values (2,'A','jack','Y')
insert into #t values (5,'b','amy','N')
insert into #t values (1,'$','adams','N')
insert into #t values (3,'*','anna','Y')
insert into #t values (7,'@','rose','N')
insert into #t values (4,'&','smith','Y')
insert into #t values (6,'!','sue','Y')
 
create nonclustered index nc_t on #t (id,ch,na)
 
-- query 1
select na from #t where ch = '!'
-- query 2
select na from #t where id = 6 and ch = '!'
-- query 3
select na from #t where ch = '!' and id = 6
-- query 4
select na from #t where flag = 'Y' and id = 6 and ch = '!'

;with tally (N) as (select row_number() over(order by id) from master..syscolumns)
select N as ID, ch, na, flag
into #bigT
from tally 
cross join #t t
where N <=100

create nonclustered index nc_bigT on #bigT (id,ch,na)

-- query 1
select na from #bigT where ch = '!'
-- query 2
select na from #bigT where id = 6 and ch = '!'
-- query 3
select na from #bigT where ch = '!' and id = 6
-- query 4
select na from #bigT where flag = 'Y' and id = 6 and ch = '!'

drop table #t
drop table #bigT

WITH cte (Num) AS
     ( 
	  SELECT 0 Num
         
		 UNION ALL
         
		 SELECT Num + 1
		 FROM   cte
		 WHERE  Num < 10000
     )
INSERT
INTO   t (id, ch, na, flag)
SELECT num                 ,
       CHAR(Num%128 + 50)  ,
       CAST(num AS VARCHAR),
       CASE
              WHEN Num%2 = 1
              THEN 'Y'
              ELSE 'N'
       END
FROM   cte OPTION(maxrecursion 10000)