Are these two queries the same - GROUP BY vs. DISTINCT?

Question

These two queries seem to return the same results. Is that coincidental or are they really the same?

1.

SELECT t.ItemNumber,
  (SELECT TOP 1 ItemDes         


        

Answer 1

If you're running at least 2005 and can use a CTE, this is a little cleaner IMHO.

EDIT: As pointed out in Martin's answer, this also performs much better.

;with cteMaxDate as (
    select t.ItemNumber, max(DateCreated) as MaxDate
        from Transactions t
        group by t.ItemNumber
)
SELECT t.ItemNumber, t.ItemDescription
    FROM cteMaxDate md
        inner join Transactions t
            on md.ItemNumber = t.ItemNumber
                and md.MaxDate = t.DateCreated