如何在SQL表中获得一组最高Foo

Question

I have a SQL table, that contains a column named Foo .

I know how to get a row with the highest Foo value, with some SQL like this:

SELECT MAX(Foo) AS HighestFoo FROM Foos;

How can I get all the rows with the highest Foo?

Answer 1

Use a subquery:

SELECT
    *
FROM
    Foos
WHERE
    Foo = (SELECT MAX(Foo) AS HighestFoo FROM Foos)

The subquery (on the last line) selects out the highest value, and then uses that value to modify the WHERE clause.

Answer 2

An alternative approach (for those db's that support it) is to use dense_rank() over()

SELECT
      *
FROM (
            SELECT
                  *
                , DENSE_RANK() OVER (ORDER BY FOO DESC) AS rnk
            FROM tblFoo
      ) AS sq
WHERE rnk = 1

Answer 3

With CTE As (
SELECT MAX(Foo) AS HighestFoo
       FROM Foos
)
Select * From Foos Where Foo = ( Select HighestFoo From CTE)