Thursday, October 15, 2009

OOW09 and my favorite 11gR2 feature

I decided to wait until the end of Oracle Open World 2009 before I posted anything. So many people have been tweeting and blogging and shooting video of this year's event, I figured I'd put in my two cents worth at the end.

Man...it's been a l-o-n-g week. I don't know if it's my increasing age or what, but being in a herd of this size for an entire week has left me feeling somewhat bruised (both physically and mentally). I started at 9am on Sunday morning by attending Tom Kyte's keynote for Oracle Develop and have made it through Thursday - which seems like a minor miracle somehow. But I have survived!

So much goes on here, it's hard to keep moving through it given the mass of people and multiple session locations (not to mention the after hours opportunities for fun and frolic). Add a bit of rain (some kind of monsoon as it seemed to me) and, at times, it was like being in an undersized kennel filled with wet dogs. :)

The sessions I attended, and there were many, were all quite excellent. I sat in on most all of the 11gR2 sessions and am really amazed at many of the new features and options 11gR2 offers. My favorite is edition-based redefinition (also referred to as "online application upgrades"). This feature isn't getting nearly as much press time as some of the other more sexy things (for instance, you couldn't move 10 feet without seeing or hearing about Exadata) but as far as I'm concerned, editioning is a hugely beneficial new feature.

By the way, it is a feature, not an option. Wow...for once it's something you don't have to pay extra for! I loved that when Tom Kyte did his "10 - no 11 - top things about 11gR2" session, that he gave editioning two spots on the list. So what is editioning?

1. You can create a new edition to contain any new code changes.
2. Data changes can be made (add new columns or new tables) and the new code can safely write to the new stuff without any of it being seen by the old edition.
3. Different projections of tables are exposed via editioning views so that each edition is allowed to see only its own columns.
4. If the old edition makes data changes those changes are propogated using cross-edition triggers into the new edition's columns (or vice-versa).

The bottom-line is that now with 11gR2, if you want to make changes to procedures, packages, views, synonyms, etc, you can do it using editioning and maintain both the old (original) version as well as the new. It also means a lot less headache. Have you ever tried to CREATE OR REPLACE PACKAGE in production while the instance is in use? What happens? Well, if the package is in use, Oracle has to wait until it is no longer in use in order to replace it. So, Oracle waits. But, if new requests to use the package come in during this time, those sessions must wait also. That doesn't even begin to touch what happens if the new package causes other objects to be invalidated and thus they need recompilation also. It can be a pretty long, arduous and resource-intensive process to get something seemingly so simple done.

With editioning, a new edition is created and the modified package is compiled into that edition. No muss, no fuss...and no waiting! This is just a bit about this great feature, but I recommend you look on OTN for more info and several whitepapers Oracle has available on the topic.

There's so much more I could blabber on about, but I'll save other thoughts for other posts. All in all, it's been a good week, my presentation on Tuesday was well attended and I got great feedback, and I've got lots of great material to take back home for further review and sharing with colleagues.

3 comments:

Rajnallasamy said...

Hi Karen, Good post. I am following your blog ever since I heard about you from hotsos symposium this year. I attended OOW previous years and it was very useful. Pls blog more new stuff about 11g.Thanks!

Brian Tkatch said...

Karen, thanx for the editioning explanation.

How many companies will use editioning?

We're rewriting an application. They do "year end changes" in QA, and move them into prod at switchover time. I suggested that for the new app we should forgo all that, and slap a date or version on everything and automagically use the right one. Nope, can't do that. It has to be in QA and moved. Why? They feel safer that way.

OK, so they are clueless. Is this an isolated case? Will versioning get the same cold response? Just wondering.

Bob said...

Ref item #2. What about adding indexes to new columns without any of it being seen by the old edition? Ahh, phttt, new code developers don't use indexes.