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November 2013

OakTable World UK 2013

Just a quick post to remind people coming to UKOUG Tech13, you can also register for OakTable World UK 2013.

If you go to the page you can see the agenda and the registration form. The event is free, but you need to be registered for UKOUG Tech13!

Enjoy!

Cheers

Tim…

Difference between storage snapshots and database virtualization

Screen Shot 2013-11-11 at 7.49.21 PM

photos by Keith Ramsey and Automotive Rhythms

People are hearing more about Delphix and database virtualization. Database virtualization is where database copies can be made in minutes using thin cloning. Thin cloning  means sharing the  un-modified blocks on the file system between clones. Modified blocks are private to the clone that made the modification.

The Principle of Least Storage

We’re copying and moving redundant bits

In any application environment, we’re moving a lot of bits. We move bits to create copies of Prod for BI, Warehousing, Forensics and Production Support. We move bits to create Development, QA, and Testing Environments. And, we move bits to create backups. Most of the time most of the bits we’re moving aren’t unique, and as we’ll discover, that means they we’re wasting time and resources moving data that doesn’t need to be moved.

Unique Bits and Total Bits

Radically reducing the bulk and burden of caring for all of the data in the enterprise has to start with two fundamental realizations: First, the bits we store today are often massively redundant. Second, we’ve designed systems and processes to ship this redundant data in a way that makes data consolidation difficult or impossible. Let’s look at a few examples:

Backup Redundancy

Create Tablespace and ORA-28374

One of the projects I worked on last week was improving our processes around encryption in Oracle. I spent a lot of time becoming intimate friends with the database wallet. Late in the week while attempting to create an encrypted tablespace on an 11.2.0.3 (PSU6) system, we mysteriously ran into ORA-28374. Oddly enough we were building two identical databases in parallel using a scripted approach but only one of the databases ran into this problem. And no matter how many times I rolled back and re-ran the wallet setup script, I kept getting this same error! There are a handful of informative Oracle Support notes related to this error and one of them had the solution to my problem. However it wasn’t immediately obvious why, so I thought it would be worthwhile to write a description based on my experience.

Create Tablespace and ORA-28374

One of the projects I worked on last week was improving our processes around encryption in Oracle. I spent a lot of time becoming intimate friends with the database wallet. Late in the week while attempting to create an encrypted tablespace on an 11.2.0.3 (PSU6) system, we mysteriously ran into ORA-28374. Oddly enough we were building two identical databases in parallel using a scripted approach but only one of the databases ran into this problem. And no matter how many times I rolled back and re-ran the wallet setup script, I kept getting this same error! There are a handful of informative Oracle Support notes related to this error and one of them had the solution to my problem. However it wasn’t immediately obvious why, so I thought it would be worthwhile to write a description based on my experience.

Reverse Key

Here’s one of those little details which I would have said just couldn’t be true – except it’s in the manuals, and the manuals happen to be right.

APPEND_VALUES and SYS_DL_CURSOR Hints with HCC

The APPEND_VALUES hint was introduced in 11.2 to allow direct path inserts with variables using the VALUES clause. i.e.

INSERT INTO XYZ (COL1, COL2) VALUES (:A, :B);

The feature was designed to allow bulk inserting via arrays of 100′s or 1000′s of records in a single insert statement. Prior to 11.2, there was no documented way to do an direct path insert other than with the APPEND hint which only worked on inserts that used the SELECT clause. i.e.

INSERT INTO XYZ SELECT * from ZYX;

Sangam 13 Presentations and Scripts

Thank you all those who attended my sessions at Sangam13 -- the annual conference of All India Oracle User Group in Hyderabad. I saw many who attended all seven sessions of mine, including the super hot (literally) one for Big Data in a small room. Audience like this makes the day for any speaker; I am no exception. Your support was very much appreciated.

Here are the presentations and all the scripts for download. All presentations are in PDF format and all scripts are in a zipped file.

Thor: The Dark World

I’ve just got back from watching Thor: The Dark World.

Unlike lots of people, I actually liked the first Thor film. I also liked the character in The Avengers, so I went into the movie with high hopes. Some parts of this film are totally awesome. Some parts are a little bit boring. Some parts are like a low budget DR Who episode.

The dark elves were really cool, a bit spooky and dead tough when they were on every other planet, but put them in London and they just run around looking like dodgy extras in a Power Rangers episode. A few minutes earlier they were shooting everyone with super laser stick things and killing Gods. Now all they can do is chase people? Seriously?