SQL - Selecting the rows with max timestamp by group

Question

I have this table

SITE   S_ID   BAN   COUNT   P       V   TIMESTAMP
23     1       4    1500    0,05    50  10/05/17 09:58:22,609000000
23     3       3    800     0,05    50  10/05/17 09:58:22,736000000
23     2       3    3000    0,05    50  10/05/17 09:58:22,674000000
23     1       4    1500    0,05    50  10/05/17 15:57:04,079000000
23     1       4    1499    0,05    50  10/05/17 15:53:38,851000000
20     1       3    2000    0,1     50  10/05/17 10:57:07,172000000
20     2       3    2000    0,1     50  10/05/17 10:59:50,127000000
20     3       2    3000    0,1     50  10/05/17 11:00:39,051000000
20     4       2    3000    0,1     50  10/05/17 11:01:15,533000000

and I'm trying to obtain something like this:

SITE   S_ID   BAN   COUNT   P       V   TIMESTAMP
23     3       3    800     0,05    50  10/05/17 09:58:22,736000000
23     2       3    3000    0,05    50  10/05/17 09:58:22,674000000
23     1       4    1500    0,05    50  10/05/17 15:57:04,079000000
20     1       3    2000    0,1     50  10/05/17 10:57:07,172000000
20     2       3    2000    0,1     50  10/05/17 10:59:50,127000000
20     3       2    3000    0,1     50  10/05/17 11:00:39,051000000
20     4       2    3000    0,1     50  10/05/17 11:01:15,533000000

i.e. for every SITE the S_ID, BAN, COUNT, P, V and TIMESTAMP with the MAX(TIMESTAMP)

Answer 1

Here you go:

SELECT 
    SITE
    , S_ID
    ,BAN
    ,COUNT
    ,P
    ,V
    ,TimeStamp
FROM [Your Table Name]
INNER JOIN 
(
    SELECT 
        SITE
        , S_ID
        , MAX(TIMESTAMP) as MaxTimeStamp 
    FROM [Your Table Name] 
    GROUP BY 
        SITE 
        , S_ID
    ) AS MaxDAata ON
        MaxData.SITE = [Your Table Name].SITE 
        AND MaxData.S_ID = [Your Table Name].S_ID
       AND MaxData.TimeStamp = [Your Table Name].MaxTimeStamp