Select Most Recent States From History Table

Question

I have inherited a table with a structure something like this:

ID   Name   Timestamp   Data
----------------------------
1    A      40          ...
2    A               


        

Answer 1

Assuming there are no duplicate timestamps per name, something like this should work:

SELECT ID, Name, Timestamp, Data
FROM test AS o
WHERE o.Timestamp = (SELECT MAX(Timestamp)
                     FROM test as i
                     WHERE i.name = o.name)