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My New Youtube Channel

I have created a new youtube channel – and have uploaded some videos there already! Bookmark & Subscribe here:

More stuff is coming over the next weeks & months :-)


NB! If you want to move to the "New World" - offload your data and workloads to Hadoop, without having to re-write your existing applications - check out Gluent. We are making history! ;-)

Advanced Oracle Troubleshooting v2.5 (with 12c stuff too)

It took a while (1.5 years since my last class – I’ve been busy!), but I am ready with my Advanced Oracle Troubleshooting training (version 2.5) that has plenty of updates, including some more modern DB kernel tracing & ASH stuff and of course Oracle 12c topics!

The online training will take place on 16-20 November & 14-18 December 2015 (Part 1 and Part 2).

The latest TOC is below:

Seminar registration details:

Sqlplus is my second home, part 8: Embedding multiple sqlplus arguments into one variable

I’ve updated some of my ASH scripts to use these 4 arguments in a standard way:

  1. What ASH columns to display (and aggregate by)
  2. Which ASH rows to use for the report (filter)
  3. Time range start
  4. Time range end

So this means whenever I run ashtop (or dashtop) for example, I need to type in all 4 parameters. The example below would show top SQL_IDs only for user SOE sessions from last hour of ASH samples:

C-MOS: How to get rid of the annoying “The Page has Expired” dialog in My Oracle Support

So, how many of you do hate the dialog below?

MOS page expired dialog

Good news – there is a fix! (or well, a hack around it ;)

Before showing the fix, you can vote & give your opinion here:

How to Compose New Gmail Messages in Full Screen (instead of the tiny compose box of new Gmail)

I’m writing this (unusual) post as I am a long time Gmail user and recently I’ve seen plenty of people & articles complain about the Gmail’s new compose window (the one that shows up as a small hovering window in the bottom right of your screen):


The top google hits so far only return tips to disable the new editor completely, but I want to use the new one, just in a bigger window! There is a very easy workaround for that – and there’s no need to switch back to the old compose mode at all!

If you are using your mouse, then just:

Snapper v4.02 and the Snapper launch party video

I have fixed most of the bugs that showed up during the Snapper launch party session and uploaded the new version (v4.02) of Snapper here:

I have also uploaded the launch party hacking session video to

I have not updated the snapper documentation yet, but here are the main improvements:

A tip for lazy Oracle users – type less with ANSI DATE and TIMESTAMP SQL syntax

I am lazy, therefore if I can type less, I will type less.

Often people are surprised to see that Oracle supports the ANSI DATE and TIMESTAMP syntax in the SQL code, which allows me to shorten the lengthy TO_DATE( …. , ‘YYYY-MM-DD HH24:MI:SS’) syntax a bit. You can just type this if you want to compare some field to a date (day precision):

SQL> SELECT COUNT(*) FROM dba_objects WHERE created > DATE'2012-12-01';


SQL> SELECT COUNT(*) FROM dba_objects WHERE created > DATE'2012-01-01';


This way you can always use the standard date format regardless of any NLS settings that may say otherwise.

Asynchronous I/O for people

Ok, I’ve wanted to write this blog entry for a long time – and now it’s time!

Most of my blog readers (thank you!) are performance-minded computer enthusiasts, who care about efficiency and optimization. You’ve been tuning SQL execution plans, instance and OS configuration so that your sessions would achieve the same results with less work and also with less waiting!

You probably know to appreciate why asynchronous I/O must be enabled for busy modern databases, so that your database sessions can do I/O (talk to the storage) without actually having to wait for the I/O operations to complete! You can increase the processing throughput, by not submitting every single I/O separately and waiting for it to complete, before being able to process the results and submit the next one. Asynchronous I/O is a crucial thing for good performance.

Reminder and Public Appearances 2011

First, a reminder – my Advanced Oracle Troubleshooting v2.0 online seminar starts next week already. Last chance to sign up, I can accept registrations until Sunday :-)

I won’t do another AOT seminar before Oct (or Nov) this year. More details and sign-up here:

I have rescheduled my Advanced SQL Tuning and Partitioning & Parallel Execution for Performance seminars too. I will do them in September/October. Unfortunately I’m too busy right now to do them before the summer.

Public Appearances:

  • I will be speaking at the UKOUG Exadata Special Event in London on 18th April
  • I have submitted a few papers for Oracle OpenWorld in San Francisco as well (end of Sep/beginning of Oct), all about Exadata. Let’s see how it goes, but I’ll be there anyway, which means that I’ll probably show up at the Oracle Closed World event too!

And that’s all the travel I will do this year…

Virtual Conferences:

I’ll soon announce the 2nd EsSN virtual conference too ;-)

Free online stuff:

Perhaps in a month or so I will do another hacking session (I’ll plan 2 hours this time, 1 hour isn’t nearly enough for going deep). The topic will probably be about low-level details of SQL plan execution internals… stay tuned!

MOATS: The Mother of All Tuning Scripts!

People talk about the Oracle SQL Developer 3 being out, which is cool, but I have something even cooler for you today ;-)

I finally figured out how to convert my screen-recordings to uploadable videos, so that the text wouldn’t get unreadable and blurry.

So, here’s the first video, about a tool called MOATS, which we have built together with fellow OakTable Network member and a PL/SQL wizard Adrian Billington (of

Here’s the video, it’s under 3 minutes long. Play the video in full screen for best results (and if it’s too slow loading, change it to lower resolution from HD mode):

Check it out and if you like MOATS, you can download it from Adrian’s website site (current version 1.05) and make sure you read the README.txt file in the zip!

Also thanks to Randolf Geist for finding and fixing some bugs in our alpha code… Note that MOATS is still kind of beta right now…

P.S. I will post my ORA-4031 and shared pool hacking video real soon now, too! :-)

P.P.S. Have you already figured out how it works?! ;-)

Update: Now you can suggest new features and improvement requests here: