Problems with the OR operator

Question

Please can someone help? I have 2 tables which I can join as follows:
select nlfull0604.accountid,company,entrydate from nlfull0604,live0604 where
nlfull0604.accountid=live0604.accountid
This returns the rows I expect, however I want to get some new Companies that might not be in live0604 but will be in nlfull0604 so I have added this:
select nlfull0604.accountid,company,entrydate from nlfull0604,live0604 where
nlfull0604.accountid=live0604.accountid or (entrydate > '01-JUN-04')
The problem is I am getting thousands and thousands of rows not just the 2,000 live companies + the 50 or so new ones - probably something to do with my brackets!
Thanks very much for your help.
Regards
Andrew

Answer 1

Hello
Yes I think you're going to need to use a union, try this out...
SQL> select
  2      accountid,
  3      entrydate
  4  FROM
  5      nlfull0604
  6  WHERE
  7      entrydate > TO_DATE('30/07/2004','dd/mm/yyyy')
  8  UNION
  9  select
10      accountid,
11      entrydate
12  FROM
13      live0604;
ACCOUNTID ENTRYDATE
         1 25/08/2004
         2 26/08/2004
         3 27/08/2004
         4 28/08/2004
         5 29/08/2004
6 31/07/2004
6 30/08/2004
         7 01/08/2004
         8 02/08/2004
         9 03/08/2004
        10 04/08/2004
        11 05/08/2004
        12 06/08/2004
SQL> update live0604 set entrydate=to_date('31/07/2004','dd/mm/yyyy') where accountid=6;
1 row updated.
SQL> select
  2      accountid,
  3      entrydate
  4  FROM
  5      nlfull0604
  6  WHERE
  7      entrydate > TO_DATE('30/07/2004','dd/mm/yyyy')
  8  UNION
  9  select
10      accountid,
11      entrydate
12  FROM
13      live0604;
ACCOUNTID ENTRYDATE
         1 25/08/2004
         2 26/08/2004
         3 27/08/2004
         4 28/08/2004
         5 29/08/2004
6 31/07/2004
         7 01/08/2004
         8 02/08/2004
         9 03/08/2004
        10 04/08/2004
        11 05/08/2004
        12 06/08/2004Note that in the first run account id 6 appeared twice because the entrydate in live0604 was different to the entrydate in nlfull0604 and so it was not a duplicate, after the update, it is picked up as a duplicate.
If you have the situation where you have the same account id and 2 different entry dates in each table, you could pick the most recent(or the oldest using min) like so...
SQL> update live0604 set entrydate=to_date('31/08/2004','dd/mm/yyyy') where accountid=6;
1 row updated.
SQL> SELECT
  2      all_accts.accountid,
  3      MAX(all_accts.entrydate)
  4  FROM
  5      (
  6      select
  7     accountid,
  8          entrydate
  9      FROM
10          nlfull0604
11      WHERE
12          entrydate > TO_DATE('30/07/2004','dd/mm/yyyy')
13      UNION
14      select
15          accountid,
16     entrydate
17      FROM
18          live0604
19      ) all_accts
20  GROUP BY
21     all_accts.accountid;
ACCOUNTID MAX(ALL_AC
         1 25/08/2004
         2 26/08/2004
         3 27/08/2004
         4 28/08/2004
         5 29/08/2004
6 31/08/2004
         7 01/08/2004
         8 02/08/2004
         9 03/08/2004
        10 04/08/2004
        11 05/08/2004
        12 06/08/2004
HTH