ROWNUM 'error'

Here's a trivial and almost pointless example of 'incompatible' implementation of Oracle's commonly used 'rownum':

Oracle:

SQL> SELECT rownum FROM T1 WHERE ROWNUM = 2;

< no rows returned >



DB2 v10:

db2 => select rownum from T1 where rownum = 2;

ROWNUM
--------------------
1

1 record(s) selected.



See the 'strange-ness'? :)

We have a match for rownum = 2 , but DB2 returns '1' as the resultset.



No, this is not a bug. This is a consequence of the 'workaround' of Oracle's 'rownum' in DB2. This, in practice, is inconsequential, because no Oracle programmer would write something like 'rownum = 2' ;) Ok, maybe some do. Those who do that deserve to get some bugs in their code anyway ;)