SQL Selecting record with highest ID

Question

I have a issue with some SQL that I can't wrap my head around a solution.

Right now the query I am running basically is:

SELECT Q.ID, Q.STATUS, C.LASTNAME, C.FIRSTNAME, 
       C.POSTAL, C.PHONE 
FROM QUEUE Q 
LEFT OUTER JOIN CUSTOMER C ON Q.ID = C.APPID 
WHERE C.LASTNAME LIKE 'SMITH%'

I have about 200 records from this query. My issue is the same person has multiple occurances.

Q.ID  Q.STATUS   C.LASTNAME   C.FIRSTNAME   ETC...
 1        A         SMITH        JOHN
 2        A         SMITH        RYAN
 3        B         SMITH        BRIAN
 100      A         SMITH        RYAN
 200      A         SMITH        RYAN

What I need returned instead is

Q.ID   Q.STATUS   C.LASTNAME   C.FIRSTNAME   ETC...
 1        A          SMITH         JOHN
 3        B          SMITH         BRIAN
 200      A          SMITH         RYAN

Can anyone point me in the right direction please. I have tried

SELECT WHATEVER FROM TABLE WHERE Q.ID IN (SELECT MAX(ID) FROM TABLE WHERE BLAH BLAH) 

which worked when searching for "RYAN SMITH" specifically. But I need to show all results for SMITH with the highest IDs.

Any help is appreciated.

Cheers

Answer 1

I guess you could do something like below

SELECT WHATEVER FROM TABLE 
WHERE Q.ID IN 
    (SELECT MAX(ID) FROM TABLE 
     WHERE BLAH...BLAH 
     GROUP BY C.FIRSTNAME, C.LASTNAME)

Hope this helps!!

Answer 2

have you tried something like that? well it is not really a SQL statement, just showing the idea

select * from Table where id in (
         select max(q.id) from Table group by c.lastname, c,firstname
)

Answer 3

If I understand well, this should work:

SELECT Q.ID
     , Q.STATUS
     , C.LASTNAME
     , C.FIRSTNAME, 
     , C.POSTAL
     , C.PHONE
  FROM QUEUE Q 
  join CUSTOMER C ON Q.ID = C.APPID 
 WHERE C.LASTNAME like 'SMITH%'
   and not exists (SELECT *
                     FROM CUSTOMER innerCustomer
                    WHERE innerCustomer.LASTNAME like 'SMITH%'
                      and innerCustomer.APPID > C.APPID
                  )

Note: I have change "left join" by "inner join" because you are filtering per C.LASTNAME. So I think left join doesn't have many sense.

Answer 4

Assuming there is a CUSTOMER.ID, and I think I'm right, here it goes:

SELECT Q.ID, Q.STATUS, M.LASTNAME, M.FIRSTNAME, 
       M.POSTAL, M.PHONE 
FROM QUEUE Q 
LEFT OUTER JOIN (
  SELECT C2.ID CID, 
         MAX(C2.FIRSTNAME) FIRSTNAME, 
         MAX(C2.LASTNAME) LASTNAME, 
         MAX(C2.POSTAL) POSTAL,
         MAX(C2.PHONE) PHONE,
         MAX(Q2.ID) QID
  FROM QUEUE Q2 
  LEFT OUTER JOIN CUSTOMER C2 ON Q2.ID = C.APPID 
  WHERE C2.LASTNAME LIKE 'SMITH%'
  GROUP BY C2.ID
) M ON (M.QID = Q.ID)