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VirtualBox 4.3.14

Oracle have given birth to VirtualBox 4.3.14. Mother and baby are doing well, with the downloads and changelog in the usual places.

Happy upgrading…



PS. Looks like the baby might be still-born. Fails pretty badly on Windows 7 at the moment…

PPS. Seems to work fine on Mac and Linux (Fedora 20)…

Using Database In-Memory Column Store with Complex Datatypes (1)

The Oracle database version, with the In-Memory option, isn’t yet released, but a lot of detail is already out there since it’s announcement by...
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Oracle Midlands : Event #4 – Summary

What a cracking Oracle Midlands event!

The evening started with a session on “Designing Efficient SQL” by Jonathan Lewis. The first few slides prompted this tweet.


When someone asks me a question about SQL tuning my heart sinks. It’s part of my job and I can do it, but I find it really hard to communicate what I’m doing. Jonathan’s explanation during this session was probably the best one I’ve ever heard. Rather than trying to explain a million and one optimizer features, it’s very much focussed on a “What are you actually trying to achieve?” approach. It should be mandatory viewing for all Oracle folks.

After the break, where I stuffed myself with samosas, it was on to the lightning talks (10 mins each).

What books by what authors should I read?

I’ve been asked the same question by multiple people, around what books by what authors are good to have, so let me answer it once here. :)

The answer is easy – it depends! Are you interested in database administration? Application development against an Oracle database? Technical apps? Functional apps? High Availability? Enterprise Manager? No single author covers all of those – unless you count the Oracle documentation set as a single author.

Deferrable RI – 2

A question came up on Oracle-L recently about possible locking anomalies with deferrable referential integrity constraints.

Exadata storage indexes and DML

Last week I’ve gotten a question on how storage indexes (SI) behave when the table for which the SI is holding data is changed. Based on logical reasoning, it can be two things: the SI is invalidated because the data it’s holding is changed, or the SI is updated to reflect the change. Think about this for yourself, and pick a choice. I would love to hear if you did choose the correct one.

First let’s do a step back and lay some groundwork first. The tests done in this blogpost are done on an actual Exadata (V2 hardware), with Oracle version (meaning bundle patch 6). The Exadata “cellos” (Cell O/S) version is on both the compute nodes and the storage nodes.

Downloading VirtualBox VM “Oracle Enterprise Manager 12cR4″

Strangely enough those cool VirtualBox VM machine downloads are nowadays a bit scattered on different Oracle places on and others. So in all that...
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EMC XtremIO – The Full-Featured All-Flash Array. Interested In Oracle Performance? See The Whitepaper.

NOTE: There’s a link to the full article at the end of this post.

I recently submitted a manuscript to the EMC XtremIO Business Unit covering some compelling lab results from testing I concluded earlier this year. I hope you’ll find the paper interesting.

There is a link to the full paper at the bottom of this block post. I’ve pasted the executive summary here:

Tuning EM12c, the OMS, Part II

We went over a few of the Java “tuning” options last time, so let’s go onto the OMS tier for this post.

Invoker Rights in Oracle Database 12c : Some more articles

I wrote about the Code Based Access Control (CBAC) stuff in Oracle Database 12c a while back.

I’ve recently “completed the set” by looking at the INHERIT PRIVILEGES and BEQUEATH CURRENT_USER stuff for PL/SQL code and views respectively.