Select All Columns By Most Recent Date and Highest Version - sql-server-2008

Question

I have been stumped on this for quite awhile. Request#, SlotId, Segment, and Version all make up the primary key. What i want from my stored proc is to be able to retrieve all rows by passing in the Request # and Segment, but for each slot i want the most recent effective date on or before todays date and from that i need the highest version #. I appriciate your time.
Values in database
Request# SlotId Segment Version Effective Date ContentId
A123 1 A 1 2012-01-01 1
A123 2 A 1 2012-01-01 2
A123 2 A 2 2012-02-01 34
A123 2 A 3 2012-02-01 24
A123 2 A 4 2015-01-01 6 //beyond todays date. dont want
Values I want to return from my stored proc when i pass in A123 for Request # and A for Segment.
A123 1 A 1 2012-01-01 1
A123 2 A 3 2012-02-01 24

Answer 1

The query could be written like this:
; WITH cte AS
( SELECT Request, SlotId, Segment, Version, [Effective Date], ContentId,
ROW_NUMBER() OVER ( PARTITION BY Request, Segment, SlotId
ORDER BY Version DESC ) AS RowN
FROM
tableX
WHERE
Request = #Req AND Segment = #Seg --- the 2 parameters
AND [Effective Date] < DATEADD(day, 1, GETDATE())
)
SELECT Request, SlotId, Segment, Version, [Effective Date], ContentId
FROM cte
WHERE Rn = 1 ;

Answer 2

Consider this:
;
WITH A as
(
SELECT DISTINCT
Request
, Segment
, SlotId
FROM Table1
)
SELECT A.Request
, A.SlotId
, A.Segment
, B.EffectiveDate
, B.Version
, B.ContentID
FROM A
JOIN (
SELECT Top 1
Request
, SlotId
, Segment
, EffectiveDate
, Version
, ContentId
FROM Table1 t1
WHERE t1.Request = A.Request
AND t1.SlotId = A.SlotId
AND T1.Segment = A.Segment
AND T1.EffectiveDate <= GetDate()
ORDER BY
T1.EffectiveDate DESC
, T1.Version DESC
) as B
ON A.Request = B.Request
AND A.SlotId = B.SlotId
AND A.Segment = B.Segment