--> 测试数据: @表A
declare @表A table (a1 int,a2 int,a3 int)
insert into @表A
select 5,9,7 union all
select 1,3,4 union all
select 2,6,1

declare @s varchar(10) set @s='1,5,8'

select a1,count(1) as cnt from 
(
select a1 from @表A union all
select a2 from @表A union all
select a3 from @表A 
) a where charindex(','+ltrim(a1)+',',','+@s+',')>0 
group by a1
/*
a1          cnt
----------- -----------
1           2
5           1
*/