10046.pl by Clive Bostock


This is a reposting of an old blog post that was on dboptimizer.com but is no longer accessible

More trace file analyzer tools at  http://ba6.us/node/177

Related blog post: Oracle “Physical I/O” ? not always physical

Often when I have a 10046 trace file, especially when looking at I/O issues, I want a histogram of I/O response time.  To get I/O response time I’ve hacked out incomple awk scripts from time to time, (more...)

Put Delphix on your laptop at Oracle Jan 28 !



Create an army of clone databases and applications in minutes


Tomorrow Jan 28 we will be installing Delphix on people’s laptops at the BIWA conference at Oracle conference center at Oracle head quarters in Redwood Shores.


  • Laptop, either
    • Mac: VMware Fusion or VirtualBox
    • Linux: VMware Fusion or VirtualBox
    • Windows: VMware Workstation or VirtualBox
  • at least 8 GB RAM
  • at least 50 GB free disk space, but preferably 100 GB free
  • at least 2 Ghz CPU, (more...)

Succeeding with Test Data Management



Screen Shot 2015-01-26 at 6.00.46 PM
Test data management is difficult, time consuming and expensive leading to incorrect implementation of test data management and significant losses in revenue from high QA costs to bugs in production. Fortunately there is a solution that alleviates the majority of the huge resource, time and planning of conventional test data management and that new technology is called data virtualization.
Dependable QA testing requires that code be tested on data that represents the data (more...)

5 ways to boost your career with Social Media


Photo by Kevin Dooley

If you are in the Bay Area tomorrow, Jan 27, come see myself, Yann Ropars and Yury Velikanov talk about how to leverage social media to boost your career. We will be talking at Oracle head quarters at the NoCOUG/BIWA conference at 2:30 pm 

Why use social media as an IT technician? Because

vibrant social networks are key to landing jobs, moving forward in your career, and securing personal happiness – (more...)

You’re Cleverer Than You Think

I often train experienced developers in new tools, and I’ve found that most underestimate what they can do – their actual skill level is higher than their own perceived skill level.

Skill development

This is different from new developers, who tend to overestimate their skills.

The reason this happens to most experienced people is the “loss of control” feeling overcomes the feeling of accomplishment. If you are very skilled with one tool, you are acutely aware that (more...)


Disjunction (logical OR) is known to cause various performance problems, from extreme parse times (e.g. here) to sub-optimal plans. A common solution to such problems is getting rid of OR’s by “OR expansion” (i.e. rewrite via UNION ALL), although it doesn’t work in 100% cases. In this post, I will consider an example of an OR problem that can be solved differently.

Here is the setup:

create table t(
   id number,
   x  (more...)

Share your interesting SQL or PL/SQL experience on stage, on camera, or in print

If you have had interesting experiences with SQL or PL/SQL in your career, here’s your opportunity to share them on stage, on camera, or in print. Send your stories to contact_nocoug@nocoug.org and we’ll forward them to the SQL evangelists team headed up by Steven Feuerstein. You may be selected to tell your stories on stage at the YesSQL! presentation at the winter conference next Tuesday or your stories may be recorded on camera or (more...)

Hardware is Cheap, Developers are Expensive

When advising customers on ADF projects, I often find development environments where many or all developers are working against the same database. That introduces a hard dependency between different parts of the project – if one developer deploys a defective PL/SQL package to the database, nobody else can run the application.

This approach made sense back when hardware was expensive and databases had to be managed by high priests in glass-walled, climate-controlled rooms. Today, you (more...)

Moving from Procedural to Set-Based Thinking

Most people who are new to working with databases tend to think procedurally. That is: I have a table that I need to update, so:

  • Find the first row
  • Update the relevant columns with the relevant values
  • Find the next row
  • Update the relevant columns with the relevant values
  • Find the last row
  • Update the relevant columns with the relevant values

People who are familiar with databases and set-based thinking would simply do:

Oracle Node.js Database Driver

I’ve been eagerly awaiting the first release of the Official Oracle Node.js Driver and Christopher Jones (@ghrd) just tweeted this –


So I hopped over to the Github repository to take a look and try it out…

…I’m very impressed so far…

Back in 2014, I presented at KScope on “Oracle APEX + Node.JS – A Primer” where I showed many demos on just how you can integrate Node.JS (more...)

Free Version of Delphix !

Delphix is now available for  30 day trial direct download ! ( if you would like a longer version please contact me at kyle@delphix.com year trials and even indefinite trials  potential possible for partners, bloggers, Oracle Aces etc)

Just got to the

The Delphix download trial consists of 3 pre-configured virtual machines downloadable as OVA files

Inappropriate behaviour

You pick up little funny things in the day to day with Oracle.

Like this one when you try to drop a tablespace with a queue table in it:

drop tablespace MY_TSPACE including contents
ERROR at line 1:
ORA-00604: error occurred at recursive SQL level 1
ORA-24005: Inappropriate utilities used to perform DDL on AQ table

You would think that since you’ve asked to drop everything, that well…everything could be dropped, but (more...)

Data Pump import makes me crabby

I’m sitting here watching the import of a moderately sized database via transportable tablespaces.  You know…the thing you use when a full export / import would be too slow, and this is meant to be … well…fast.

And fast it is.. until it reaches the following step:


Now understandably, there’s plenty of stats to import, so its fair that it should take a little while.  But a quick look (more...)

Top 3 criteria to choose a data virtualization solution 

mirror_reflection_ copy

Data virtualization solutions also known as Copy Data Management (CDM), Copy Data Virtualization (CDV) and Data Virtualization Appliances (DVA) are rising rapidly as over 100 of the Fortune 500 have adopted data virtualization solutions between 2010 and end of 2014. Adoption is hardly surprising given that data virtualization reduces the time to provision copies of large data sets from days down to minutes and eliminates most of the space required (more...)

Slow external table access

We had an interesting issue on, where users were reporting very slow performance on queries to external tables. When I tried to replicate the problem, everything seemed just fine, so I initially reported back the familiar "Well, it works on my PC" :-) [Just kidding]

Anyway, connecting by proxy to one of their accounts, did reveal the error, which suggested something to do with privileges.  A sql trace revealed that (more...)

Oracle Flashback – Empowering Power Users!

Flashback feature of Oracle database has been of interest to me since its inception in 9i. Thank you OTech Magazine for publishing my article on Flashback in the winter edition. Read the article here. There are several excellent articles in this edition of the Magazine. More than 100 pages of tech content. Don’t miss!! Merry Christmas! […]

“Innovation in Managing the Chaos of Everyday Project Management” is now on YouTube

If you missed Fishbowl’s recent webinar on our new Enterprise Information Portal for Project Management, you can now view a recording of it on YouTube.


Innovation in Managing the Chaos of Everyday Project Management discusses our strategy for leveraging the content management and collaboration features of Oracle WebCenter to enable project-centric organizations to build and deploy a project management portal. This solution was designed especially for groups like E & C firms and (more...)

Disruptive Innovations



photo by Tsahi Levent-Levi

by Iggy Fernandez

excerpted from The Twelve Days of NoSQL (http://iggyfernandez.wordpress.com/)

NoSQL and Big Data are “disruptive innovations” in the sense used by Harvard professor Clayton M. Christensen. In The Innovator’s Dilemma: When New Technologies Cause Great Firms to Fail, Christensen defines disruptive innovations and explains how they eventually lead to the failure of the established players who ignored them:

“Generally, disruptive innovations were technologically (more...)

Do You Know It All?

Last week’s Technology That Fits newsletter (sign up here) stimulated some interesting discussions. I showed the following graphic:

Doomed Projects

Everybody agreed that projects that choose good tools for good reasons are good, and projects that choose bad tools for bad reasons are bad. But some disagreed on Learning and Lucky categories above.

I call projects that choose good tools for bad reasons “lucky”. They are CMMI level 1 – sometimes they succeed, sometimes they fail, and they (more...)

Simplicity Is Good!

by James Morle

This article is about the importance of appropriately simplistic architectures. I frequently get involved with the creation of full-stack architectures—in particular the architecture of the database platform. There are some golden rules when designing such systems, but one of the most important ones is to keep the design as simple as possible. This isn’t a performance enhancement; this is an availability enhancement. Complexity, after all, is the enemy of availability.

Despite it (more...)