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April 2012

Fedora 17 Alpha…

I’ve just tried the alpha of Fedora 17 to see if the GNOME 3 software rendering works and it did. You may recall, since updating my graphics card I’ve been forced to use the fallback mode on Fedora 16. I’m quite keen to move back to proper GNOME 3, which looks like it will be possible when F17 is released.

On a VM it seems a little on the slow side, so I hope this isn’t an indication that it will be annoying on my desktop. I guess time will tell. Fingers crossed though.



Another Oracle internals hacking session about how Oracle parameters work – tomorrow! :-)

Ok fellow internals geeks, tomorrow’s going to be another 1-hour hacking session (which will probably take 2 hours) with me. It’s about how Oracle parameters work and all the different types of them too. See the registration link for more info:

Date: 12 april 2012

Time: 9am Pacific (see in other timezones here)

Reproducing a Canned Report using a Single SQL Statement

April 11, 2012 I recently received an interesting request for assistance from an ERP email mailing list.  The author of the email wanted to reproduce a canned report found in the ERP package so that the information could be published on a Microsoft Sharepoint system.  The author of the email is using SQL Server for [...]

IOT Secondary Indexes: Primary Key Considerations (Beauty And The Beast)

As discussed previously, one of the nice features of an IOT Secondary Index is that it contains the mandatory Primary Key of the IOT, which is always maintained and can be used to access the necessary rows of the IOT regardless of  row movement within the IOT itself. This can also be beneficial if only the PK [...]

Upcoming Events

I'll be doing four public events in the next week and a half or so.

The first one is open to anyone - anywhere.  I'll be doing a live webinar on MAA - the Maximum Availability Architecture.  It will take place this Thursday April 12th at 10am PDT.  You should register online before then if you are interested.

After that, I'll be off to Belfast Ireland to do a repeat of what I presented at Oracle OpenWorld in October.  This will be done in conjunction with Oracle and the UKOUG.  See for details, it'll take place on Monday April 16th.

Column Groups - Edge Cases

Oracle 11g added Extended Statistics support for column groups in order to detect correlated columns for filter predicates using an equal comparison.

Note that Oracle 11g also added the ability to use the number of distinct keys of a composite index as an upper limit for the cardinality estimates for matching column predicates, which means that the optimizer is now capable of detecting correlated columns without the explicit addition of Extended Statistics / Column Groups.

Friendly Reminder - Free Webinar

This is just a friendly reminder that tomorrow my free Webinar on Cost-Based Optimizer Basics will take place at

Repairman Jack : Hosts

Hosts is the fifth book in the Repairman Jack series by F. Paul Wilson.

Jack is reunited with his sister, just as a new virus threatens to link all human brains into a single collective hive mind, turning the human race into a docile petri dish living for the greater good of the virus.

Perhaps it’s my mood, but this story is just a little too depressing for my tastes. I’m hoping the rest of the series won’t degenerate into this type of doom and gloom. It needs a little more wit and humor to lift it.



Stats Collection

This is just a temporary note to point you to a poll set up by Timur Akhmadeev to get an idea of how people are handling stats collection in newer versions of Oracle.



Here is a poll prompted by today twitter talks on the default METHOD_OPT value (which is ‘for all columns size auto’ since 10g) and automatic statistics gathering job (auto-task since 11g). CBO development team suggests to use the default job to gather statistics with default options. Do you use the job exactly this way with real production databases? I’m very interested to see some numbers. Please share the poll link so that more people vote. Thanks.