How do you group by one column and retrieve a row with the minimum value of another column in T/SQL?

Question

So I know this is a pretty dumb question, however (as the rather lengthily title says) I would like to know how do the following:

I have a table like this:

Answer 1

Another option would be something along the lines of the following:

DECLARE @TEST TABLE(    ID int,    Foo int,    Bar int,    Blagh int)
INSERT INTO @TEST VALUES (1,10,20,30)
INSERT INTO @TEST VALUES (2,10,5,1)
INSERT INTO @TEST VALUES (3,20,50,70)
INSERT INTO @TEST VALUES (4,20,75,12)

SELECT Id, Foo, Bar, Blagh 
FROM (
      SELECT id, Foo, Bar, Blagh, CASE WHEN (Min(Bar) OVER(PARTITION BY FOO) = Bar) THEN 1 ELSE 0 END as MyRow
      FROM @TEST) t
WHERE MyRow = 1

Although this still requires a sub-query it does eliminate the need for joins.

Just another option.