Compare two tables based on two columns

Question

Hi,
my tables looks like this:
Desc Table A (account)
Account1_id
Account2_id
name,
empid
Table B (Bill )
BillNo
Advertiserid
agencyid
total vvalue
I need to pick up total value from table B where the unique combination of advertiser-Agency id is the same as the given account1_id -Account2_id combination in table A for each employee id.
In other words my output should be like
Empid | Account_id (should be same as advertiserid)| Account2_id (same as agencyid) | sum(total_value) for this adv-agency combination.....
objective: Get the total value from table B for each unique account1-account2 combination (advertiser-agency in other words) .
I am not sure if I should use a coreelated subquery or how to handle the situation....Right now I am just checking the two columns separately like this:
select.......from a,b
where b.advertiser_id = a.account1_id and b.agencyid = b.account2id
Is it correct to do so? I have a feeling that I am missing something if I join them seperately like this......Any advice on this?
I am using Oracle 10g. Hope I am clear.Please let me know. Thankx in advance.

Answer 1

Here you go:
SQL> WITH bill AS
  2  (
  3          SELECT 1000 AS billno, 101 AS advertiserid, 102 AS agencyid, 5000 AS total_value FROM DUAL UNION ALL
  4          SELECT 1001, 101, 103, 5000 FROM DUAL UNION ALL
  5          SELECT 1002, 101, 102, 1000 FROM DUAL
  6  ), account AS
  7  (
  8          SELECT 101 AS account1_id, 102 AS account2_id, 'John' AS name, 50 AS empid FROM DUAL UNION ALL
  9          SELECT 101, 103, 'James', 40 FROM DUAL UNION ALL
10          SELECT 101, 105, 'Joe', 60 FROM DUAL
11  )
12  /* End Sample Data */
13  SELECT a.name
14       , a.empid
15       , a.account1_id
16       , a.account2_id
17       , SUM(b.total_value)
18  FROM   account a
19  JOIN   bill    b ON  a.account1_id = b.advertiserid
20                   AND a.account2_id = b.agencyid
21  GROUP BY a.name
22         , a.empid
23         , a.account1_id
24         , a.account2_id
25  ;
NAME                 EMPID          ACCOUNT1_ID          ACCOUNT2_ID   SUM(B.TOTAL_VALUE)
John                    50                  101                  102                 6000
James                   40                  101                  103                 5000