SQL. Is there any efficient way to find second lowest value?

Question

I have the following table:

 ItemID Price
    1   10
    2   20
    3   12
    4   10
    5   11

I need to find the second lowest price. So far, I have a query that works, but i am not sure it is the most efficient query:

select min(price)
from table
where itemid not in
(select itemid
from table
where price=
(select min(price)
from table));

What if I have to find third OR fourth minimum price? I am not even mentioning other attributes and conditions... Is there any more efficient way to do this?

PS: note that minimum is not a unique value. For example, items 1 and 4 are both minimums. Simple ordering won't do.

Answer 1

SELECT MIN( price )
FROM table
WHERE price > ( SELECT MIN( price )
                FROM table )