get any hightest value in table

how about

SELECT TOP 3 FROM salaryTable ORDER BY salary DESC

Result:
4 500
9 450
3 400
2 350
1 300
8 200

then use the data record of the result with the appropriate index
0 = highest
1 = second highest
2 = third highest
and so on...

(if you want more than 3 records change the sql query)

You can use a CTE as temp table like this, say 3rd highest:

With cte0(id, salary) 
AS
(
select top 3 * from tablename order by salary DESC
)
select top 1 * from cte0

learn more: Common Table Expressions(CTE) in SQL SERVER 2008[^]

Try

SELECT * /*This is the outer query part */
FROM myTable Emp1
WHERE (N-1) = ( /* Subquery starts here */
SELECT COUNT(DISTINCT(Emp2.Salary))
FROM Employee Emp2
WHERE Emp2.Salary > Emp1.Salary)

Here N is the nth maximum you want e.g. 2nd or 3rd maximum salary.

If you are using SQL Server 2012, the answer is slightly easier.

SELECT * FROM myTable
ORDER BY Salary DESC
OFFSET N ROWS

Use row number over function, order by salary.