OraNA.info upgraded

Eddie Awad just announced that he has improved functionality of Oracle Blogs aggregator OraNA.info. Now it shows post from long history, not only last 20. It is now really usable.
And if you are Oracle Blogger, go and join OraBloggers group on Google groups.

Cheers, Paweł

Polish Students won ACM Programming Contest

Today students from Warsaw University won ACM-International Collegiate Programming Contest. They solved 8 tasks out of 10, see Final results.

Congratulations to my compatriot,
Paweł

Technorati

I've just created my Technorati Profile, so this post is just to interrelate this blog with my Technorati account.
Paweł

Bug 5705795 - AMAZON-LIKE ?

Today I've reviewed list of 10.2.0.3 patch 1 for Windows and i've noticed bug with name: 5705795 - MANY CHILD CURSORS CREATED FOR AMAZON-LIKE WORKLOAD IN 10.2.0.3. I was aware of this bug as it was mentioned in note 403616.1 on Metalink. I do not think it's good idea to use customer name in bug description. From this I can assume:

• Amazon is using latest Oracle Database,

• Amazon is running on Linux or Windows (as this bug is only for these platforms),

• probably Amazon is using Linux as patch for linux was released earlier,

• it gives some inside view of software design used at Amazon,

I do not think Amazon is happy with these reveals.

At least bug 5705795 is not public on Metalink.

Cheers, Paweł

Interesting posts 2007-02-06

Here are some interesting posts I've read recently:

• User Interface Design: Complexity vs. Flexibility - Rob Walling is traing to find aswer to question: can a design be simple and flexible at the same time?
• How to scale... Tom Kyte post about scalability of middleware and database. Do not forget to read Tim Hall response Middle-tier diet….
• Difference between Jeff Bezos and Bill Gates? by Kathy Sierra - very interesting story about top CEO's attitude to users.

Cheers, Paweł

The Palm: The Eighth Wonder of World

You must definitely see The Palm: The Eighth Wonder of World. Incredible...

Paweł

13 – Happy or Unhappy Number?

This is my 13 post. So I’ve decided to make some digression. Usually number 13 is considered as unhappy. It seems not a rule for me. This year 13 is my happy number. On 13th January I’ve signed new job contract. It was just about 13:15 (or might be it was exactly at 13:13). What is more interesting, sum of digits in that date (13-01-2006) is equal to 13 (1+3+0+1+2+0+0+6=13). Number of building I’m now working in is also 13. As for now I’m quite happy in my new job.
Also according to Walter Schneider 13 is definitely happy number. I’ve observed that for me the unhappiest day in month is 26th. In fact it is 2*13. When I use Walters method to it gives me: 26 => 40 (2*2+6*6) => 16 => 37 => 58 => 89 => 145 => 42 => 20 => 4. So 26 is unhappy number and it confirms my observations :).
More on Happy Numbers in Wikipedia.

Cheers, Paweł

ORA_ROWSCN continuation…

In my previous post I was wondering how SCN is assigned to ROW or Block. I couldn’t find explanation in Oracle Documentation. But I’ve found this document written by Jonathan Lewis. You should read this! I’m little afraid about 'best guess' technology.
By the way you can also read article about undocumented userenv('commitscn') written in May 1999. When I first saw it I thought it might be replaced by ORA_ROWSCN.
So I’ve try this:

SQL> create table t (n1 number, text varchar2(10)) ROWDEPENDENCIES;

Table created.

SQL> insert into t values (userenv('commitscn'), 'T1');

1 row created.

SQL> select ora_rowscn, n1 commitscn, text from t;

ORA_ROWSCN  COMMITSCN TEXT                                                     
---------- ---------- ----------                                               
             4621851 T1                                                       

SQL> declare
 2    pragma autonomous_transaction;
 3  begin
 4    insert into t values (userenv('commitscn'), 'TAuto');
 5    commit;
 6  end;
 7  /

PL/SQL procedure successfully completed.

SQL> select ora_rowscn, n1 commitscn, text from t;

ORA_ROWSCN  COMMITSCN TEXT                                                     
---------- ---------- ----------                                               
             4621851 T1                                                       
  4621852    4621851 TAuto                                                    

SQL> commit;

Commit complete.

SQL> select ora_rowscn, n1 commitscn, text from t;

ORA_ROWSCN  COMMITSCN TEXT                                                     
---------- ---------- ----------                                               
  4621854    4621853 T1                                                       
  4621852    4621851 TAuto

So for sure ORA_ROWSCN and userenv('commitscn') is not the same. I must say that I’m even more confused.

If You have some spare time, I recommend to read this post: Is it crazy to feel guilty about success? and from Eddie Awad blog: SYS_OP_MAP_NONNULL, REVERSE, LNNVL, NVL, NVL2, COALESCE

Cheers, Paweł

Binary Days

As addition to may previous post lets see other Binary days, where day number is power of 2.

SQL> select rownum-1 power_of2
  2  , to_char(trunc(sysdate,'YYYY')-1+power(2,rownum-1),
  3    'DD-MON-YYYY DAY')  magic_day
  4  from dual connect by level <=9;

 POWER_OF2 MAGIC_DAY
---------- ---------------------------------------------------------
         0 01-JAN-2006 SUNDAY
         1 02-JAN-2006 MONDAY
         2 04-JAN-2006 WEDNESDAY
         3 08-JAN-2006 SUNDAY
         4 16-JAN-2006 MONDAY
         5 01-FEB-2006 WEDNESDAY
         6 05-MAR-2006 SUNDAY
         7 08-MAY-2006 MONDAY
         8 13-SEP-2006 WEDNESDAY

9 rows selected.

Interesting coincidence - there are only 3 days of week: SUNDAY, MONDAY and WEDNESDAY.

BTW. Does anybody know if is it possible to turn off these automatic <br /> tags in beta blogger?

Paweł

Programmers Day

Today is 256th day of year. It is considered as Programmers Day. Let's celebrate...

Cheers, Paweł

Kubica 3rd in F1 race

Well Done
Polish driver Robert Kubica in his 3rd race in Formula 1 took 3rd place on Monza in Italy. This is really BIG SUCCESS as he is driving Formula 1 car for few weeks in races only.
Well done Robert. Keep it that way...