Feed aggregator

Histogram problems

Stephen Booth - Sun, 2006-11-19 14:31
A question just appeared on the Oracle-L mailing list about whether there are any issues with using histograms. I've seen a number of presentations over the last couple of years that have warned about issues where you have histograms on highly skewed data and use bind variable (or have cursor_sharing=force, which synthesises bind variable from literals in queries), so I responded:On 19/11/06, A Stephen Boothhttps://plus.google.com/107526053475064059763noreply@blogger.com0

dbms_job, pended and drifting

Dong Jiang - Thu, 2006-11-16 15:26

Suppose we have a job submitted, interval is sysdate + 1 / 24 / 60, but the job is going to take 5 minutes, how will Oracle behave?
Looks like the sequence of events will be the following:
T0, Job #1 starts, the next run time is going to be sysdate(T0) + 1 minute.
T0 + 1 minute, The next job #2 starts, but is blocked by a QS lock, id2 in v$lock will tell the job id.
T0 + 5 minute, Job #1 completes, set sys.job$.next_date=greatest(T0 + 1/24/60, sysdate), effectively changing the this_date for job #2 to be sysdate. Job #2 starts.
Another issue is T0 is loosely guarenteed and could be off by couple of seconds, and even if the job completes within interval, the start time could drift if one uses sysdate only. To avoid drifting, use some calculation based on trunc(sysdate) instead of sysdate.

Null object_id in user_objects

Dong Jiang - Thu, 2006-11-16 13:09

When will Oracle have a null object_id, even if the doc says it’s NOT NULL?

An invalid database link.

An update: Actually, any database link.
It comes from the second branch of the union-all clause of user_objects:
select l.name, NULL, to_number(null), to_number(null),
l.ctime, to_date(null), NULL, ‘VALID’, ‘N’, ‘N’, ‘N’
from sys.link$ l
where l.owner# = userenv(‘SCHEMAID’);


Denis Goddard - Thu, 2006-11-16 00:22
Well, well, well.... apparently I have a "Boston or New Hampshire" accent.
I am QUITE sure it's a "New Hampshire" accent, thank you very much!

The strange thing is... my 2-year old son already has an almost ridiculous New England accent. He says "heyah" for "here", "cah" for "car", and so forth. The weird thing is, we can't figure out how he picked it up. We almost never watch TV, and when we do it's not local news, so the accent didn't come from there. He has had this accent ever since he started talking, just 1-2 months after we moved to Nashua.

Anyways, I'm from Wisconsin but my dad is from England (with a long spell in Canada) and he has a sort of vaguely British accent, which I assume I inherited slightly.

What American accent do you have?
Your Result: Boston

You definitely have a Boston accent, even if you think you don't. Of course, that doesn't mean you are from the Boston area, you may also be from New Hampshire or Maine.

The West
The Midland
North Central
The Northeast
The Inland North
The South
What American accent do you have?
Take More Quizzes

UKOUG 2006 - Day 1

Stephen Booth - Tue, 2006-11-14 18:35
Today was the first day of the United Kingdom Oracle User Group 2006 conference. The day itself was pretty good, lots of good talks (more on that later), but I ran into a couple of issues in the evening. The first issue was when I went into the Handmake Hamburger just accross the canal from the ICC, I was alone and the waitress/Maitre d' said they didn't have any free tables suitable for one Stephen Boothhttps://plus.google.com/107526053475064059763noreply@blogger.com0

Which source control system are you using?

Christian Shay - Tue, 2006-11-14 16:38
As part of our planning for our next release of the Oracle Developer Tools for Visual Studio .NET, we'd like to know which source control system(s) your company currently uses.

I'm running an informal poll over at the ODT OTN Forum... please click through that link and let me know which source control system you are using! Thanks!

Sun releases three new open source modules to the Grid Engine project

Siva Doe - Tue, 2006-11-14 14:30

This announcement came from SuperComputing 2006


It will be interesting to see how the Windows as execution node is received.


100,000 more?

Robert Vollman - Tue, 2006-11-14 10:48
18 months.107 posts.110,000 reads.Not too long ago I reacted with humble incredulity that 10,000 people had read what I had to say about Oracle.Here I am, exactly one year later, and there have been 100,000 more visits. I'm almost afraid to continue, will I be talking about 1,000,000 in November 2007?I wonder why people are reading my blog because, despite how numerous we are, it seems like Robert Vollmanhttp://www.blogger.com/profile/08275044623767553681noreply@blogger.com3

Some books might make you think wrong

Mihajlo Tekic - Sat, 2006-11-11 10:59
It is amazing how confusable some of the books could be.
You better check any information you think is different than you know.
Currently I am reading a book that is suppose to prepare me for OCP exam.
There are some questions and answers after each Chapter. I found few answers that I think are not correct.
Don’t get me wrong I still think that the book I read is a good one.

One Example: (I changed usernames and sequence name used in the original question):

The following SQL statement will allow user test_usr which operations on sequence scott.test_sq?
GRANT ALL ON scott.test_sq to test_usr;

A) Select the next value from scott.test_sq
B) Alter sequence scott.test_sq to change the next value
C) Change the number of sequence numbers that will be cached in memory
D) Both A and C
E) All of the above

The answer provided in the book is D.

But, I think it is E. Why?

SQL> conn scott/*****
scott@ora10g> create sequence test_sq
2 start with 1
3 increment by 1;

Sequence created.

scott@ora10g> select test_sq.nextval from dual;

scott@ora10g> conn sys as sysdba
sys@ora10g> create user test_usr identified by test_usr
2 default tablespace users
3 temporary tablespace temp;

User created.

sys@ora10g> grant connect, resource to test_usr;

Grant succeeded.

sys@ora10g> grant all on scott.test_sq to test_usr;

Grant succeeded.

sys@ora10g> conn test_usr/test_usr
test_usr@ora10g> select scott.test_sq.nextval from dual;


test_usr@ora10g> alter sequence scott.test_sq
2 increment by 10;

Sequence altered.

test_usr@ora10g> select scott.test_sq.nextval from dual;


test_usr@ora10g> alter sequence scott.test_sq
2 increment by 1;

Sequence altered.

test_usr@ora10g> conn scott/*****
scott@ora10g> select test_sq.nextval from dual;



Database Tools Talks at UKOUG next week

Donal Daly - Thu, 2006-11-09 14:03
Next week I'll be in Birmingham at the UK Oracle User Group Conference. I am looking forward to it, as it gives me another opportunity to talk about our new tools. This year, I think the database tools team is well represented.

Mike Hichwa, VP of Database Tools (main architect behind Oracle Application Express & my boss!) will be giving a presentation on Thursday morning @ 9am titled - An Insight into SQL Developer and Application Express

Sue Harper, PM for SQL Developer is giving a presentation on Wednesday on SQL Developer: Using Oracle's Graphical Database Development Tool. As you probably know by now, we have released an evaluation copy of SQL Developer 1.1 on OTN, so I am sure Sue will cover all the new cool features in 1.1 and answer any questions you might have.

Alex Keh, a PM whose focus is on our windows technologies is giving a presentation on Tuesday about .NET and Oracle Best Practices: Performance, Deployment and PL/SQL Tips. So if your preferred development environment is .NET be sure to attend his talk. I think we do a lot to make a .NET developers experience productive with Oracle database technology.

For myself, lucky me has 3 presentations!

On Tuesday I will be talking about: End the Microsoft Access Chaos - Your simplified path to Oracle Application Express. I will be demoing our new Oracle APEX Application Migration Workshop. This should also be making an appearance on OTN real soon...

Then on Thursday, I have two presentations: Oracle Application Express: Features, Futures and Customer Tales In this presentation, I give a brief overview of Application Express, What's in 2.2, what's coming in 3.0 and some demos and finally Oracle Migration Workbench: Taking Database migration to the next level where I will demo the new Oracle Migration Workbench integrated into SQL Developer. This should be making an appearance on OTN in 2007.

I am also looking forward to hearing customer feedback at the Oracle Development Tools Roundtable on Wednesday afternoon.

Having had a look at the agenda there are many talks which I want to attend. Looks like it is going to be a good week. Now to put the finishing touches to my presentations...

Firefox search plug-in for Oracle

Dong Jiang - Wed, 2006-11-08 05:47

Talking about firefox search-plugins for Oracle, you can find some here.
I like the Oracle Docs by Eddie Awad and AskTom by Stefan H.

Oracle SQL Developer v1.1 Evaluation Release goodies

Dong Jiang - Wed, 2006-11-08 05:41

Oracle SQL Developer v1.1 Evaluation Release is out. New Feature List here.
Some goodies I like are

  1. NLS preferences, my pet peeve
  2. View CLOB data
  3. Export data to HTML
  4. Search Engines, for OraDoc, AskTom, etc. Could augment firefox search plug-ins
  5. Autotrace

Now it’s time to upgrade and try out.

Ah, LiveHTTPHeaders

Dong Jiang - Tue, 2006-11-07 10:26

Ok, I did not abandon this blog, just I don’t have much to blog about, especially in Oracle, as I am now deep in Cognos territory.
Just noticed this cool firefox extension.
I knew such an extension must exist, but just didn’t find it. It would have been night and day difference for me when I was writing up the Cognos black-box test mentioned here. Unfortunately, I did it the hard way. Don’t laugh, but I just have the following Javascript snippet to print all the HTML elements in the form.

var elements = document.forms[0].elements;
var counter = 0;
for (counter=0; counter < elements.length; counter++) {
  alert(elements[counter].name + '=' + elements[counter].value + '\n');

I won't get much work done this weekend....

Donal Daly - Sat, 2006-11-04 16:22
Not a work related post, but...

I was asked by the Porsche club of Ireland (of which I am a member) would I be willing to write a car review for their newsletter as the Irish Porsche dealership offered them a car for the weekend. I could pick what I wanted, so I went for a 997 C4S manual.

In the picture is my son Daragh, and Alan from the Porsche dealership. In Ireland cars have high taxes , so this car costs €160K/$203K.... The car is on my insurance, so I have to be careful :-)

I had promised Julie I would sort out the garden this weekend and deal with all the leaves, sorry not this weekend!

I think I'm in love with UPK

Jo Davis - Fri, 2006-11-03 13:18
Yeah, I know - I've been lax lately - no posts! So on Thursday of course I spent the day at the Red Rock Leadership Forum and one of my collegues gave a demo of the User Productivity Kit which Peoplesoft had (and has now been ported across to Oracle Apps and JD Edwards too). All I can say is - WOW! Everything I dreamed Tutor would do for my life.... but this actually seems to do it :)

Documentation, training and testing - three of my favourite things in the world. And the UPK makes training material (instructor led and online) and gives you those detail level, field-by-field test scripts that everyone seems to be totally keen on printing and storing somewhere (despite my preference for concentrating your efforts on effective scenario-based testing). And more importantly it does it faster than anything else I've seen!

Needless to say, our Peoplesoft guys at work got a pretty good laugh at the Oracle Apps consultants over this one - we're all madly in awe, they've been using the thing for years of course! So the UPK developer is now on my laptop and my adventures in the land of UPK begin today (well technically last night, which is when I started downloading it as the zip file is a massive 405309KB according to my computer - it's still extracting as I type).

So will my love-at-first-sight affair with this software come crashing into an evil wall of reality? Possibly.... I'll let you know

OpenWorld .NET Slides, Source Code, 64-bit ODP.NET and 64-bit .NET Stored Procedures

Christian Shay - Thu, 2006-11-02 23:47
It's been a very busy news week! As promised, here are all of the .NET and Windows OpenWorld slidedecks and sourcecode including the .NET and Oracle Hands on Lab.

Another big piece of news: we just released the beta of the 64-bit ODAC (for both x64 and Itanium). I know many of you have been waiting for this! This includes the 64-bit Oracle Data Provider for .NET as well as support for .NET Stored Procedures with Oracle Database 10g for 64-bit Windows.

Have a look and tell us what you think!

Join us at Microsoft TechEd Europe and UKOUG

Christian Shay - Tue, 2006-10-31 17:00
Oracle is once again a platinum sponsor of Microsoft Tech·Ed Europe (Barcelona, November 7-10) and we will be demoing our latest features integrating with Microsoft Windows and .NET. If you are attending, be sure to drop by the Oracle booth for a demonstration and attend an Oracle session.

Developing and Optimizing .NET Applications for Oracle 10g
Presenter: Alex Keh
Thursday November 9th from 15:45-17:00

Oracle Booth Demos
Oracle Developer Tools for Visual Studio .NET
.NET Stored Procedures
Oracle Database on Windows
Grid Control for Microsoft Servers
Application Server For Microsoft Servers

Alex will also be presenting at UKOUG (Birmingham, November 14-17) . His talk is on Tuesday November 14th at 11am:
.NET and Oracle Best Practices: Performance, Deployment and PL/SQL Tips

Other Windows related sessions you should check out:
Oracle 10gR2 RAC on Windows Server 2003 x64: Best Practices, Tuning and Administration
Apples and Oranges - Comparative Performance Studies on Linux and Windows

I also happened to notice some cool SQL Developer and Application Express sessions hosted by Oracle engineering staff:
SQL Developer: Using Oracle's Graphical Database Development Tool (Wed Nov 15th, 16:35)
An Insight into SQL Developer and Application Express (Thur Nov 16th 9am)
Oracle Application Express: Features, Futures and Customer Tales (Thurs 10:20)

My next post will include slides and code from Oracle OpenWorld, so stay tuned!!!

Free Webinar: Competing on Analytics

Marcos Campos - Tue, 2006-10-31 06:37
I blogged some time ago (link) about an article on The Harvard Business Review by Babson College's Tom H. Davenport on how analytics are becoming a key competitive factor for companies. I have just learned that Prof. Davenport is giving a free webinar today. The theme is "Competing on Analytics." What participants will learn:What data-driven marketing is (and isn't)How marketing visionaries like Marcoshttp://www.blogger.com/profile/14756167848125664628noreply@blogger.com0
Categories: BI & Warehousing

The biggest Openworld ever closed its doors - and what a great time it was

Clemens Utschig - Tue, 2006-10-31 03:36
Last week was definetely insane! 40.000 customers, 10! locations around San Francisco, and more than 1600 sessions, all dedicated to the power of information sharing.

As most of my team, I litterally spent the whole week at Oracle World, as we constantly went back and forth from the demo grounds, to Oracle Develop, located at the Hilton, and customer meetings.

The first highlight? The SOA Suite distribution (for all number junkies, it's made it also in time, to be released to OTN (here) - yeah!

In a nutshell, what did happen?
.. and the who is who of IT came by to contribute a keynote (john chambers, michael dell, and many others), plently of analysts gathered to ask about this and that - and from customers we got overwhelming feedback.

Also a bunch of whitepapers made it in time for Oracle World, perfectly in line with Thomas' Keynote on standards. They can be found here

My sessions on "Integrating Content DB with Oracle BPEL Process Manager", "Advanced BPEL" and "SOA in the real world" - were very well attended, and especially overwhelming was the crowd interested in the advanced stuff on BPEL, covering themes like transactions, compensation, fault handling and BPEL 2.0.

.. and while blogging here from some 34000 feet - somewhere over England en route to Germany, my laptop battery is going down, mostly because of the non working poweplugs on LH 455, whatever .. I'll blog more on OOW when I get the pics that friends took during the week.

Oracle Data Mining in Argentina

Marcos Campos - Mon, 2006-10-30 19:22
I spent the week of the 18th in Buenos Aires spreading the word on Oracle Data Mining. I was invited by Snoop Consulting as a keynote speaker at their Update' 06 (warning, the site is in Spanish) event. Snoop Consulting has a very capable technical team. They are positioning themselves to become a leading company of added-value services for information technologies in the region, focused mainly Marcoshttp://www.blogger.com/profile/14756167848125664628noreply@blogger.com0
Categories: BI & Warehousing


Subscribe to Oracle FAQ aggregator