I know this is a much asked question and I've had a look through whats already available but I believe my case is slightly unique (and if it's not please point me in the right direction).
I am trying to find the latest occurrence of a row associated to a user a currently across two tables and several columns.
table: statusUpdate
+-------+-----------+-----------+-------------------+
| id | name | status | date_change |
+-------+-----------+-----------+-------------------+
| 1 | Matt | 0 | 01-01-2001 |
| 2 | Jeff | 1 | 01-01-2001 |
| 3 | Jeff | 2 | 01-01-2002 |
| 4 | Bill | 2 | 01-01-2001 |
| 5 | Bill | 3 | 01-01-2004 |
+-------+-----------+-----------+-------------------+
table: relationship
+-------+-----------+--------------+
| id | userID |stautsUpdateID|
+-------+-----------+--------------+
| 1 | 22 | 1 |
| 2 | 33 | 2 |
| 3 | 33 | 3 |
| 4 | 44 | 4 |
| 5 | 44 | 5 |
+-------+-----------+--------------+
There is a third table which links userID to its own table but these sample tables should be good enough to get my question over.
I am looking to get the latest status change by date. The problem currently is that it returns all instances of a status change.
Current results:
+-------+---------+-----------+-------------------+
|userID |statusID | status | date_change |
+-------+---------+-----------+-------------------+
| 33 | 2 | 1 | 01-01-2001 |
| 33 | 3 | 2 | 01-01-2002 |
| 44 | 4 | 2 | 01-01-2001 |
| 44 | 5 | 3 | 01-01-2004 |
+-------+---------+-----------+-------------------+
Expected results:
+-------+-----------+-----------+-------------------+
|userID |statusID | status | date_change |
+-------+-----------+-----------+-------------------+
| 33 | 3 | 2 | 01-01-2002 |
| 44 | 5 | 3 | 01-01-2004 |
+-------+-----------+-----------+-------------------+
I hope this all makes sense, please ask for more information otherwise.
Just to reiterate I just want to return the latest instance of a users status change by date.
Sample code of one of my attempts:
select
st.ID, st.status, st.date_change, r.userID
from statusUpdate st
inner join Relationship r on st.ID = r.statusUpdateID
inner join (select ID, max(date_change) as recent from statusUpdate
group by ID) as y on r.stausUpdateID = y.ID and st.date_change =
y.recent
Hope someone can point me in the right direction.