What is the SQL statement that removes duplicates but keep additional column's data?

Question

Hello:

I'd like to know what should be the SQL statement (for ORACLE DBMS) that would get back unique (by CUSTOMER_ID, VEHICLE_ID, DEALER_ID and EVENT_TYPE_ID) rows BUT it will return the latest date (EVENT_INITIATED_DATE) for that row too. I've tried DISTINCT and GROUP BY, but wasn't able to figure out how to handle EVENT_INITIATED_DATE (that is DATE data type).

CUSTOMER_ID            VEHICLE_ID             DEALER_ID  EVENT_TYPE_ID          EVENT_INITIATED_DATE      
---------------------- ---------------------- ---------- ---------------------- ------------------------- 
22197630               23093399               6040       20                     11-JAN-07                 
22197630               23093399               6040       5                      11-JAN-07                 
22197630               23093399               6040       4                      11-JAN-07                 
22197630               23093399               6040       3                      11-JAN-07                 
22197630               23093399               6040       4                      19-JAN-06                 

Answer 1

select CUSTOMER_ID, VEHICLE_ID, DEALER_ID, EVENT_TYPE_ID, 
    max(EVENT_INITIATED_DATE)
from MyTable 
group by CUSTOMER_ID, VEHICLE_ID, DEALER_ID, EVENT_TYPE_ID

Answer 2

Distinc won't work.

Group by - and then one of the MAX / MIN etc. functions for the additional fields.

SELECT Customer_ID, VEHICLE_ID, MAX(EVENT_INITIATED_DATE)... ...GROUP BY Customer_ID, VEHICLE_ID

Hope that helps ;)