Parallel Rollback

I had a user call up and ask to kill a session which was causing him grief and hence I killed it without much thought since it was not a Production system

A few hours later I noticed that SMON was doing parallel txn recovery. This was validated by the view
select * from x$ktprxrt;

Unfortunately I have lost the output but it did show that it would take eons

But this was also confirmed from the pstack of smon which included the function ktprbeg which I believe begins parallel rollback. (Snippet below)

[syd0904:oracle:OSTA1]/u01/app/oracle => pstack 11905
11905: ora_smon_OSTA1

0000000100d80868 (more...)

Oracle recommends optimizer_mode=choose

Here is a challenge: Find the place in the latest Oracle product documentation that states the following “To improve response time, verify that the optimizer_mode Oracle initialization parameter is set to choose.”

The first person to tell me in person where Oracle is recommending this, wins a beer. E-mail (more...)

Unexpectedly honest job posting

I recently joined the Oracle Connections group on Linked-In and I'm getting regular daily mails with job postings and searches for work. Mostly harmless, but I've just seen a great one:

(You may need to be a member of Linked-In and/or the Oracle Connections group to follow the link).

I think we've all been there, confRigurating away to our heart's content, haven't we? It certainly explains a lot of the problems we see in production.

Available January

I've just discovered that my current contract, with a healthcare company in Hampshire, will not be extended beyond the end of the year. So, in the current economic climate, I've decided to start a blog in order to drum up more business.

My primary skills are in troubleshooting and tuning Oracle systems, from entire databases to individual SQL queries.

If you have an application running on an Oracle database and you need someone to investigate an issue on that system, get in touch.

"My name is Peter Moore. I am a professionally qualified and highly experienced database administrator with extensive (more...)

"When All Else Fails…"

This is on a shirt that I received as a present at work today.

How to find the particular Data Dictionary Table or Dynamic Performance View (V$)?

Dear Blog Readers,

Even though we use some of the important Data Dictionary Tables and Dynamic Performance (V$) views regularly, sometimes we fall short to recall a particular view, i.e. It’s not easy to remember all the dictionary views.

And also, many times, it’s been asked by novice in the OTN Forums that

What is the view to find the information about data files, tablespaces, etc.,?

What are the list of Data Dictionary (more...)

SCJP 6 Upgrade Exam (310-056)

by Fábio Souza Guys and girls, I guess the best way to start this post is with my appologies. I really wanted to post it earlier, but you all know how things are =P. It has been almost three months...

This is a summary only. Please, visit the blog for (more...)

ODTUG podcast, SQL Developer Data Modeling

Did you know that ODTUG is podcasting? I hear a couple of podcasts on the way to work the other day, and they’re good. I encourage you to sign up at

The latest episode was an interview with Sue Harper about the upcoming SQL Developer 2.0, (more...)

10g Migration Ramification Part 2: Making the database a safer place

In Part 2, I will be discussing a couple of the security changes Oracle has made in 10g Release 2 that have affected my life as a DBA. (I can't speak to 10g Release 1 as I pretty much skipped this release altogether). As a whole, these changes point to Oracle's continuing focus on database security, although it could be argued they have a long way to go.

Changes to the DEFAULT profile:
Oracle has made a change to the out-of-the-box setting of FAILED_LOGIN_ATTEMPTS of the DEFAULT profile. In 9i the default setting was UNLIMITED, however, in 10gR2, (more...)

Article:Managing Complexity with BPEL Environment

SOA World published an article on BPEL Management written by me with Arvind Maheshwari.

You can read the article: Managing Complexity with BPEL Management!

Being unreasonable (Bug in PL/SQL Web Services)

If you have a lot of PL/SQL packages, it should be real easy to publish them as Web Services – after all, JDeveloper contains a nice wizard for exactly this purpose.

I expected that a lot of people were already using this functionality, so I was very surprised to find (more...)

Index Dynamics – Part 3

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See previous post Index Dynamics - Part II or first part Index Dynamics - Part I

On this part, I’m going to share with you the final results for my 2 week experiment with indexes on their habitat, a production environment.

I’ve to forewarn that some data was not available, as the ANALYZE method fails for objects currently locked, given that our environment is a “live” production database and for consistency we scheduled all tests for a given time, which some days collided with business process. The Used Space graph shows those NA data points; (more...)

Our "Friend" ORA-01555

Have you ever had your Oracle program ever get the dreaded ORA-01555: snapshot too old: rollback segment number 10 with name "_SYSSMU10$" too small error, you rerun the program, and it runs to completion with no errors? No changes to the code. No changes to the program parameters. No changes to the database. You just rerun the program and it works. As an application developer I would just say that the DBA needs to increase the amount of snapshot space and leave it up to the DBA to handle it. But since it is not a re-creatable event, the DBA (more...)

Payables Duplicate Invoices

| Nov 9, 2008

A common requirement that is there in almost all Payables department is to identify potential duplicate invoices. The standard Oracle report 'Invoice Audit Listing' is not effective when it comes to list down potential duplicate invoices. The 'Invoice Audit Listing' is more of a listing and the payables manager has to spend time and effort in analysing this report. Also, not to mention when it comes to performance this report takes quite a while to complete if you mention a very old 'Begin Invoice date'.

A common requirement that comes to my mind is to report all invoices which are (more...)

Received the Certification Kit of Oracle 10g RAC Expert Exam.

Dear Friends,

After a long wait, I have received the Oracle 10g RAC Expert Certification Kit in my hands today, as I have already taken this exam (1Z0-048) in the month of August-2008. More or less it took more than three months to reach in my hands.

Best of luck everyone who is preparing for the Oracle 10g RAC Expert Exam – 1Z0-048.

Check my other blog post on “How to prepare for 1Z0-048 - (more...)

How to Get/Gain Real Time Experience/Exposure as a DBA!

Dear Blog Readers,

Every now and then I do receive e-mails from the novice DBAs saying that:

“We could not perform well at the interview, as the questions were too technically based on real time requirements”

“Due to not having real time experience, we failed at the interview to explain the steps/approach to resolve the issue asked”

…… and so on

When I asked them how they prepare and practice the DBA Activities, their response (more...)

Oracle-Validated RPM on OEL 4.5

This is officially my first post on this blog.. finally after weeks of procrastination ..So here it goes..

Last August 29, 2008 on one of the RSS feeds of OTN TechBlog Sergio Leunissen posted a blog about Oracle Validated being available outside ULN which is very nice to hear.. then after 2 months (October), Alejandro Vargas posted a blog on how to do the Oracle-Validated installation on OEL5..

which then made me want to try (more...)

Enterprise Java – State of the World!

One of my friends commented: “Java is no longer cool! Not hot either! What is the current state of enterprise Java?”

First it was .Net and then came a bonanza of scripting languages such as Ruby. All these technologies were there to eclipse the popularity of Java and J2EE. (more...)

JDeveloper 11g on Mac OS-X

Today, I have been stuck at home, and it was a good opportunity for me to upgrade my current 10g release of JDeveloper to the latest and greatest, on my iMac.
So far so good, but remember the basics: read the releases notes, and Google for someone else, with past (more...)

OT: 3 Mobile Broadband doesn’t much like Gmail and Blogger

I use 3 mobile broadband in the UK (and Italy) and I have only a couple of nags about it:
  1. I can't use FireFox 3 and Gmail together over mobile broadband - I have to switch to IE7 and sometimes I have to downgrade Gmail to the simple HTML version. I have 2 gmail accounts (one work, one private) and the problem seems to be worse on the latter. The symptom is that the loading bar is followed by a blank screen and the status "Done".
  2. I simply cannot seem login to over mobile broadband - hence no (more...)