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Time (Hanging On In Quiet Desperation) !! September 14, 2010

Posted by Richard Foote in Richard's Musings.
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UPDATE: My first presentation at OpenWorld on Sunday “Session S318615: “IOUG Oracle Indexing Tips, Tricks and Traps” is now FULL. Hopefully you have already pre-registered although sometimes with these things, the presentation might be moved to a bigger room.

For those of you who may have been wondering why it’s been so quiet here lately, no, while driving home from work one dark evening, I haven’t been taken by aliens on board their mothership, to a beautiful but mysterious galaxy far far away, to be experimented on and mind probed into why earthling indexes in Oracle databases need to be rebuilt so infrequently …

I’ve just been really really busy !!!

The InSync10 Conference in Melbourne last month was excellent, a really good 2 days and it was nice to catch up with lots of my Oracle friends such as John Bushell, Tom Kyte, Connor McDonald, Mogens Norgaard, Debra Lilley, Kyle Hailey, Penny Cookson, Jeannie Dobney, Tony Jambu, as well as meeting lots of other nice people as well. My talk was well attended (considering the stiff competition) and seem to go well considering the nice feedback I’ve received.

However, the biggest thrill of all was catching up with Stanley the ACE vest again. You can just see the excitement on my face in this picture of me with Stanley !!

Since then it’s been non-stop. I’ve been on Oracle training courses, I’ve been finalising my presentations for OpenWorld, updating my seminar materials for the upcoming seminars in Europe next month, in heavy training trying to overcome various injuries so I can compete in the football final series (we managed to make the grand final again this year only to be beaten by Canberra FC 0-1), helping kids with their homework revision (I had forgotten just what fun maths and simultaneous equations can be !!), trying to learn and experiment and pick up as much 11g release 2 knowledge as I possibly can at work ready for our upcoming upgrades, and on and on it goes.

So unfortunately, my poor little blog has been rather sad and neglected lately as a result.

Things don’t appear to be slowing down anytime soon with my packing nearly done for my trip to Oracle Openworld nearly upon me !! I’m again really looking forward to catching up with lots of people in San Francisco, should be another excellent experience. Received an email recently from Oracle marketing to say that my first presentation on the Sunday is filling up fast, which is nice to know. My agenda is:

Session S318615: “IOUG: Oracle Indexing Tips Trick and Traps” – Sunday September 19, 12:30pm Moscone West L2 Room 2005

Session S319069: “Oracle Indexing New Features In Oracle11g R1 and R2″ – Monday September 20, 2:00pm Moscone South Room 303

“Unconference: Oracle Indexing Q & A With Richard Foote” Tuesday 21 September, 10:00am Hotel Parc 55 Mason Room

Hopefully, I’ll have the chance to catch up with a lot of you in the coming week at OpenWorld.  To gurantee a place in the first two sessions, I would recommend booking ASAP via the Scheduler Builder facility.

A sad thing about going to Oracle OpenWorld this year however is that I’ll miss my local rugby league team, the Canberra Raiders playing a home final against the Western Tigers. I’ve a feeling this could finally be our year and I’ll miss on most of the final series while in the US. Go the mighty Green Machine !! Hopefully, I’ll be back in time to watch them win the grand final.

Finally, just want to quickly mention the Michigan OakTable Symposium 2010 Conference that’s on this week. I would dearly love to go but my schedule made it impossible. However, it’s a fantastic conference with a truly quality list of speakers and if you have the chance to go, I would strongly recommend grabbing that chance.

Hoping to write a few blog posts in the coming days, to complete my little series on block dumps, to write a few things from OpenWorld, cover some of the nice little goodies from 11g that are index related and review the fantastic deluxe re-release of the classic David Bowie album, “Station to Station”.

But for now, it’s back to the packing and making sure I have enough undies for the trip to OpenWorld 🙂

World Cup, Insync10 and Coming Index Block Dumps July 12, 2010

Posted by Richard Foote in InSync10, Richard's Musings, World Cup.
4 comments

Well after a month of watching the World Cup during these long cold Canberra nights, my beloved Spain have finally, at long long last, after years and years of bitter disappointment and despair, have deservedly won the World Cup !! Iniesta, you legend, you will never have to buy a drink ever again, whenever or wherever you walk into any bar in Spain !!

Life now just isn’t going to be quite the same again …

My dream now is for Australia to both host the World Cup in 2022 and to win it one day as well.

With Cadel Evans now leading the Tour de France, perhaps I have a few more weeks of sporting late nights ahead of me still …

For those of you in Australia, just a reminder that the InSync10 Conference in Melbourne is fast approaching. I’ll be both attending and presenting this year and will be joined by a host of great speakers including Tom Kyte, Mogens Norgaard, Debra Lilley, Steven Feurestein, Connor McDonald, Kyle Hailey, Guy Harrison and Penny Cookson to name but a few. Should be a great event and I strongly recommend making it to Melbourne if you can.

My session on “Indexing New Features in 11g R1 & R2” is in Room 106 on Tuesday, 17 August 10:00am-10:45am.

I’ll soon be posting a series on Index Block Dumps, discussing how to read and interpret them and how they can be incredible useful in learning not only how Oracle indexes actually work and behave but also the internals to many core Oracle concepts such as row level locking, concurrency and read consistency.

But for tonight, a long night’s sleep finally awaits. Buenos noches …

Collaborate 2010: Here I Come (Red Money) April 15, 2010

Posted by Richard Foote in Collaborate 2010, Richard's Musings.
5 comments

Just a short note to say I’ll be attending and presenting at next weeks Collaborate 2010 Conference in (hopefully) sunny Las Vegas.

I’ll be presenting my latest version of Oracle Indexing Tips, Tricks and Traps which was a big hit when I presented it recently at the Hotsos Symposium.  Details are:

Session ID: 302

Date: Monday, April 19

Time: 10:45am-11:45am

Location: Surf D

As with all good presentations, the room is filling up fast so make sure you book your seat early 🙂  Hopefully, I get the opportunity to meet some of you at the conference. Please stop and say hello.

I’m really looking forward to spending some time again in Las Vegas, meeting up with some other Oracle ACEs and taking the opportunity to catch a few shows.

If plans go well and Black 26 finally pulls through and gives me a break, who knows, I might yet retire afterwards … 🙂

New Additions To My Blogroll January 24, 2010

Posted by Richard Foote in Richard's Musings.
2 comments

Thought it was time to update my blogroll with a couple of new additions.

Both Charles Hooper and Randolf Geist have provided excellent advice and information on the OTN forums for quite some time and both have excellent blogs that are well worth checking out.

They’re also both co-authors in a new Oracle book I’m keen to get my hands on-  Expert Oracle Practices: Oracle database Administration From The Oak Table.

My next series of posts will look at how Oracle implements row-level locking and achieves the magic that is read consistency.

For the point of view of indexes of course !!

Coming soon, after I’ve finished writing and updating a few new presentations and white papers while watching the Australian Open tennis.

The CPU Costing Model: A Few Thoughts Part V (Reality) January 13, 2010

Posted by Richard Foote in CBO, Multiblock Reads, Oracle Cost Based Optimizer, Richard's Musings, System Statistics.
5 comments

There’s plenty more I could talk about regarding the CBO CPU costing model and system statistics but I’ll make this my final little comment on this subject for now.
 
As previously discussed, the CPU costing model basically takes the time it takes to perform the all necessary I/O related activities and all the time it takes to perform all necessary CPU related activities and adds them together to get the overall time to complete a task. The CBO then takes this total and divides it by the average time to perform a single block I/O so that it expresses the overall costs in units of single block I/Os.
 
There are two advantages with expressing CBO costs in this manner.
 
Firstly, it makes the move from the old I/O costing model a little easier in that the “units” of cost under both CBO costing models is very similar.
 
With the I/O costing model, the unit of cost was also basically the number of I/Os. It’s just that the CBO made no (automatic) distinction between the I/O costs associated with single and multiblock reads. The cost was simply the expected total number of I/Os for a given execution plan, with single block and multiblock I/Os being consider the same (unless the optimiser_index_cost_adj parameter kicked in).
 
With the CPU costing modelling, the costs are expressed specifically in units of single block I/Os. However, the CBO automatically takes into consideration and differentiates the relative costs associated with multiblock I/Os (and CPU operations) and incorporates them automatically into the final cost.

The other nice advantage is that one can use the actual cost values as an indication of how long an operation or execution plan is likely to take. The overall execution times of the plan are divided by the average time of a single block I/O when using the CPU costing formula. Therefore by multiplying these cost values out again by the average time of a single block I/O (SREADTIM system statistic), one can have an indicative idea of the overall expected execution time.
 
The overall execution times as estimated by the CBO using the CPU costing model is therefore basically = cost of execution plan multiplied by SREADTIM system statistic.
 
Using my previous example with the FTS where the overall cost of the execution plan was 70, and the SREADTIM system statistic was 5:
 
the overall execution time as estimated by the CBO is approximately 70 x 5 = 350 ms.
 
Now this of course is only an indicative value. As all system related statistics are simply averages, there could obviously be discrepancies with how long specific I/Os take to actually perform, the size and number of specific multiblock read operations, etc. There may also be caching characteristics of objects that may influence the actual number of physical reads and associated wait times, it doesn’t take into consideration time taken to actually return data to the “client”, etc. etc. etc.
 
However, it provides one with a rough “ballpark figure”. If the actual executions times in the above example were (say) 20 seconds, then it’s a strong indication that the CBO may have got it wrong, that it may have calculated the wrong cost and maybe as a result the wrong execution plan. Somewhere, something such as the segment statistics, the system statistics, optimizer parameters, etc. may be inaccurate and is causing the CBO to get its costings incorrect.
 
The CBO cost value doesn’t compare well to reality and so is perhaps worthy of further investigation.
 
The cost values associated with CPU costing model is not some random, ambiguous, mysterious number but a value that can often be derived and which can be most useful in determining and resolving problematic SQL statements and execution plans.

Merry Christmas (Peace On Earth) December 23, 2009

Posted by Richard Foote in Christmas, David Bowie, Richard's Musings.
7 comments

Wow, yet another year almost behind us and what looks like being yet another busy year ahead. Can you believe that The Noughties are nearly all gone, I remember being all excited at the dawn of The Eighties !!

I must say I’m really looking forward to finally saying “Twenty Ten” rather than the more long-winded “Two Thousand and Nine” 🙂

I just want to wish everyone a very very Merry Christmas and a fantastic, fun-filled, index rebuild free, very very happy New Year in 2010.

Hopefully next year, Australia will win the Football World Cup, Crystal Palace will finally get promotion to the Premier League, England will be 4-0 down in The Ashes (again) with just one match to go, David Bowie will release a new album and the world will be just that little bit cooler and less polluted.

Here’s hoping anyways, as I’m sure are all the Polar Bears as well; certainly the Aussie, Crystal Palace supporting ones with good taste in music 😉

As is my custom, no Christmas would be complete without a bit of David Bowie and Bing Crosby to bring some good cheer. This year, a lovely fully restored version of their classic performance for your viewing pleasure:

“Our finest gifts we bring, pa rum pum pum pum” indeed 🙂

Collaborate 2010: Penny Lane December 18, 2009

Posted by Richard Foote in Collaborate 10, Richard's Musings.
5 comments

Well, so much for my plans to not travel as much next year …

Found out earlier in the week I’ve now been selected to present at next year’s Collaborate 10 event in Las Vegas. I’ll be presenting a new version of my Indexing Tricks and Traps presentation on Monday, 19 April from 10:45am to 11:45am (Session 302).

I’ve been to Las Vegas a number of times but this will be my first Collaborate conference. Back in 1989, I even managed to leave Las Vegas with more money than when I arrived 🙂

So if you don’t get the chance to catch me at Hotsos Symposium 2010, perhaps I’ll see you at Collaborate 10 !!

Hotsos Symposium 2010 December 9, 2009

Posted by Richard Foote in Hotsos Symposium, Richard's Musings.
1 comment so far

I’ve attended and presented at numerous Oracle conferences and events over the years but one conference I’ve never had the opportunity to attend is the Hotsos Symposium, held each year in Dallas, Texas, USA. It’s one of the premier Oracle events, especially for those of us DBAs with a special interest in performance tuning and management and so is a conference I’ve always wanted to attend one day.

Therefore, it’s with great pleasure and anticipation that I’ve been invited to present at next years event to be held on 7-11 March 2010. I’ll be presenting 2 presentations, Oracle Indexing Myths and Oracle Indexing Tips and Tricks.

As usual, the list of presenters next year reads like a who’s who of Oracle Performance Tuning experts from all around the world, with Tom Kyte being the Keynote Speaker and Tanel Poder conducting the optional (but highly recommended) training day. Don’t let the fact Tanel looks in the photo on the Hotsos Symposium website very much like Count von Count from Sesame Street put you off 🙂 Having had the pleasure of attending his Advanced Oracle Troubleshooting Seminar, Tanel really knows his stuff.

I look forward to catching up with all of you lucky enough to attend the Hotsos Symposium next year.

Zurich and Paris: Nice Way To Spend A Week November 10, 2009

Posted by Richard Foote in Richard's Musings, Travel.
6 comments

I’ve just returned from a bit of whirlwind visit to Europe, teaching my Index Internals Seminar in two lovely cities, Zurich in Switzerland and Paris in France.

Coming from Australia, everything is relatively new with nearly anything over a 100 years old regarded as historically significant. I therefore love visiting European cities which are so rich in history and where you can walk past buildings regarded as “new” but actually built before Australia was even discovered by the Europeans.

I’ve been to Switzerland before but never to Zurich, so I was keen to spend my free day there doing what I enjoy doing best when visiting a city for the first time, just walking and exploring. I was really lucky in that the weather on my free day was next to perfect, clear and sunny, whereas it rained on all the other days I was in Switzerland.

I started my walk from the impressive “Zurich Hauptbahnhof” (Railway Station) which is actually a lovely old building in its own right. I then made my way down the picturesque Limmat, past wonderful buildings such as St. Peter’s Church with what is considered the largest clock face in Europe, Fraumunster Church which has some of the most beautiful stained glass windows I’ve ever seen, the huge 700-800 year old Grossmunster Cathedral and the elegant Opera House.

After walking around the shores of Zurich Lake for a while, I decided to take a cruise where I just sat on the top of the ferry-boat, soaking up the sun and all the amazing views, including the massive Alps looming on the horizon. Zurich Lake certainly puts Canberra’s own little Lake Burley Griffin to shame although I can cycle around Burley Griffin during my lunchtime, not sure I could do the same around Zurich Lake. I then just walked and walked throughout the “old town” district, exploring all the lovely old buildings with their bay windows and balconies and all the narrow alleyways, squares and little market places. I of course bought some Swiss chocolates for the folks back at home.

2009 Switzerland France 047

As it grew dark, Zurich lit up and all the lovely old buildings shone with a new brilliance. The only incident I had of note was on the train back to the hotel, when the train inspector upon checking my ticket gave me a shocked look, full of disdain as I was inadvertently sitting in the first class carriage !! I was led like a naughty boy to where I belonged with all the other second class citizens. The seminar on the following days went really well with an excellent class of folk (pun of course fully intended).

Later in the week, I went to Paris to present my second seminar. Paris is a city I had previously visited, many years ago as the first destination of my honeymoon. So I had to be careful not to have too good a time, else there might be a few problems awaiting me back at home 🙂 Again I was really fortunately, having a perfect sunny day on my free day while it rained on every other day of my visit. I decided to basically walk from the Eiffel Tower to Notre-Dame Cathedral while crossing every single bridge on the Seine in between. Paris is absolutely one of my favourite cities in the world, it’s such a unique and special place. The walk was fantastic (I highly recommend it to anyone who hasn’t done it), with just so much to see and enjoy along the way. And boy are there a lot of bridges (I think I counted 14 bridges along the way), but none as impressive as the grand Pont Alexandre III.

2009 Switzerland France 108

Apart from seeing the Eiffel Tower at the start, I spent time at the charming Place de la Concorde, spent a few hours at the incredible d’Orsay Museum (incredible if you’re like me and love Impressionist Paintings by masters such as Van Gogh, Monet and Renoir), went past the one and only Louvre Museum and then onto Saint Louis Island and the stunning Notre Dame Cathedral where I spent some time just marvelling at the place.

I decided to walk all the way back, but this time exploring primarily the north bank with its shops, restaurants and sites such as Saint-Jacques Tower and Place Vendome. As it got dark, I finally made it up to the Avenue Des Champs Elysees and the famous Arc De Triomphe. To finish what was a fantastic day, I then walked all the way across back to where I had begun and the Eiffel Tower at night, so I could see it in all it’s lit-up glory and ambience, with its search beams circling the clear evening skies.

The only problem I had was being continually hassled again and again by people who kept saying I had just dropped a “golden ring” (I guess in the hope I would buy it as some sort of bargain). There must obviously be a good market for shower curtain rings in Paris …

The seminar was again great with a good crowd asking some really good questions. Everyone was very patient as I tried to not talk too fast for those whom English was a little rusty. For those that know me, talking slowly is not a skill that comes easily to me 🙂

I had a great time but thankfully, that’s all my travel over with for the forseeable future. Next year I will definitely reduce my travel commitments, spending much more time at home. Which of course also means perhaps spending more time on this blog as well 🙂

Rebuilding Indexes Every Sunday Afternoon !! October 28, 2009

Posted by Richard Foote in Index Rebuild, Oracle Indexes, Richard's Musings.
87 comments

I just had to share this amusing article on “Scheduling Oracle Index Rebuilding“.

Regular readers of this blog can no doubt pick the various inaccuracies and strawman arguments with this article. It’s was nice however to reminisce and take a stroll down memory lane back to the 80’s and 90’s when many DBAs indeed did spend every Sunday afternoon rebuilding indexes and the such during so-called maintainance windows.

However, if you’re like me and now work on sites where there is no such Sunday maintainance window because your users actually require and demand 24 x 7 access to their applications, because organisations still want to sell their products and services online during Sunday afternoons, because governments still want border control applications functioning on Sunday afternoons, because consumers still want access to their bank savings on Sunday afternoons, because police still need to access critical information about possible criminal activities on Sunday afternoons, because airlines still want to fly aircraft on Sunday afternoons, etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. etc. ……..

then perhaps the article may not be that useful to you afterall.

Of course, maybe you do have a maintainance window of some description but then have that other really annoying problem associated with modern databases, of them being big, really really big and so more difficult to maintain. Back in the 80’s and 90’s, databases were relatively small by todays standards and it was conceivable for indexes to be rebuilt with little or no thought. There was generally little point, but at least you could get away with it. However, if you’re like me and you have databases with indexes that total in the many terabytes, it just isn’t feasible or practical to rebuild all such indexes, even if you wanted to.

No. If you do have a maintainance window, you may want to make sure the valuable time is spent well, on activities that actually make a difference.

Of course you may also look after databases like I do where the percentage of indexes that actually benefit from a rebuild is not around 30% as suggested by the article but significantly below 1%. Therefore rebuilding 99+% of indexes for no practical gain or purpose may not be considered a “wise” use of maintainance opportunities.

One thing this article did make me ponder though is the number of database sites out there where the DBAs demand and force their businesses and associated end-users into having forced downtimes, into having their applications and business processes impacted and made unavailable (say) every Sunday morning, not because it’s actually necessary or because there’s a business or technical benefit but just because their DBAs say or think they still need to follow the processes and maintainance activities of the 80’s and 90’s. Interesting question that …

One last point I would make with this article (which BTW will change and be modified in the future, I can guarantee that, just save a copy and see). Why would you bother with validating the structure of all indexes if you plan to rebuild them all anyways ? And who is the more inept ? Someone in the Netherlands who attempts to run a script that attempts to validate structure of all indexes or someone who writes a script to validate structure indexes with an ALTER INDEX command 😉

Personally, I spend every Sunday afternoon relaxing and enjoying the weekend, playing sport, perhaps doing a bit of gardening and on a lovely sunny day, just sitting back with family and friends enjoying a barbecue and a few cold beers.

Meanwhile, all my database applications just run on happily along with no impact on business activities at all …

Oracle OpenWorld – Day 5 Hightlights October 16, 2009

Posted by Richard Foote in Oracle OpenWorld, Richard's Musings.
9 comments

Started the day desperate again for a coffee at the OTN lounge.

I was looking forward to catching Kevin Closson at the Unconference but unfortunately the session was cancelled at the last minute. So spent some time having a nice chat with Chris Muir and Tim Hall who I had the pleasure to meet when I attended the ODOUG conference in Monterey earlier in the year.

I then attended an excellent roundtable discussion forum with the Oracle folks who write and manage the Oracle Cost Based Optimizer. Some excellent questions (including mine on the use of AUTO with method_opt 😉  ), although I wasn’t totally convinced with the answer given. However, I had to clap and clap rather loudly when they made special mention of not setting the OPTIMIZER_INDEX_COST_ADJ paramater and recommending rather strongly not to touch this parameter at all. Something I’ve been suggesting for quite some time. I also got some encouraging feedback on resolving a couple of  key issues I have with statistics gathering:

1) A better way of collecting the clustering factor statistics for indexes so that Oracle can remember more than just the last block it visited

2) The ability to collected extended statistics that span more than one table

Both are being actively looked at. However, the highlight for me was the fact they were playing “The Best Of Bowie” album after the presentation, just for me !!

Also had the pleasure of meeting Christian Antognini in person who’s writings I greatly respect.

My final session of the day and of the conference was a round table discussion with the Oracle Real-World Performance folks, including Graham Wood who I had the pleasure to meet earlier in the conference and Greg Rahn who I also met today for the first time. Again, a very good session with some very good questions and answers, especially the question of when should one rebuild an index and the answer that one should only do so in special cases. The fact that these guys promote this best practice in a large public forum such as this (although I was picked out by the panel from the audience that perhaps I should be up there answering this question !!), can only help in getting the message out there.

And so it ends. I had a fantastic time here at Oracle OpenWorld, met some fantastic people and made still more Oracle friends, but I’m now really looking forward to getting home after over 3 weeks on the road.

Oracle Openworld – Day 4 Highlights October 16, 2009

Posted by Richard Foote in Oracle OpenWorld, Richard's Musings.
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I set out to reduce my pace today with only limited success.

My first session was to attended Alex Gorbachev and Paul Vallee’s Unconference session on how to make DBAs highly available. Interesting discussion on some of the various challenges confronting DBAs, such as controlling the balance between the need for stability and availability vs. the need of some organisations for constant change requirements and the importance of delivering such change as quickly as possible. Also, whether the procedures and processes for managing and controlling change management, including industry and governmental governance requirements are a help and a good thing or a hindrance and a threat in just getting the job done. The answer IMHO is that it depends on how such guidelines are implement and policed. It’s somehow comforting to know that other DBAs face similar issues and concerns as your own.

I then attended an excellent presentation on the new features associated with Data Guard in 11g Release 2 (except for the section where an Apple customer described his experiences with Data Guard, during which I simply couldn’t understand a single word he said). This is certainly all of great interest for us at work with the ability of being able to configure a read-only database farm having obvious business potential. However, I was particularly impressed by the ability of Oracle when confronted with a block corruption to automatically fix the corruption by copying a healthy version of the block from a standby database (or indeed the Primary database if the corruption appears on the Standby side). The key word here is automatically and without a single error message being raised, except for a message written to the alert log. Impressive stuff.

The lunch today was simply superb, absolutely the nicest lunch I can ever enjoy having. Please note these comments are addressed specifically to Chris Muir who missed out on lunch and was hungry all afternoon as a result 🙂

Then spend some time in the OTN lounge, catching up with a number of folks, including Cary Millsap. Looks like I might very well be presenting at the Hostsos Symposium next year if I can get enough free time organised.

Watched Larry’s Keynote address from the OTN lounge. I had a press pass that enabled me to watch the keynote up close but the free beers on offer at the OTN lounge convinced me this is the place to be 😉 There wasn’t a lot new announced that I didn’t already know, although the 10 million dollar Exadata challenge to IBM is typical Ellison. However the highlight for me was the speech by Arnold Schwarzenegger during the keynote, very funny.

 

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After missing out on all the prize draws yet again (I never, ever win these sorts of things, ever), I despondently made my way back to the hotel. Had a lovely dinner with my family who are over doing all the sightseeing things while I’m at the conference beforing making my way to the Oracle Appreciation Event on Treasure Island. Popped into the Aerosmith concert for 5 minutes, tick, seen them now and then over to see dear old Roger Daltrey who performed a really good set of mainly Who classics. Oracle certainly know how to put on an excellent show. However for me, the highlight was actually the coach ride to and from the event with the stunning views of the San Francisco lights as we crossed the Bay Bridge.

sadly, it all comes to an end tomorrow …

Oracle OpenWorld 2009 – Day 3 Highlights October 15, 2009

Posted by Richard Foote in Oracle OpenWorld, Richard's Musings.
6 comments

The first thing to note about day 3 is that it’s wet. I mean really really wet and really windy as well. Considering my home town of Canberra has been in drought now for many years with water restrictions in place, I haven’t seen this much rain for a very long time. That said, I believe it’s been raining quite a bit in Canberra since I’ve been traveling so perhaps things are beginning to change for the better at last.

Started the day by attending Dan Morgan’s Unconference session on 11g Rel 2 new features that don’t feature in the marketing material. Some good stuff is in there, with basic little things such as being able to now easily alter database links for example having the potential to make life a little easier.

I then presented my own Unconference Q & A session on Oracle indexes. The turn out was actually quite good and there were some really good discussions including Index Skip Scans, Locally Partitioned Indexes, dangers of Bitmap indexes, coalecing rather than rebuilding and how different it is to drop an index once it’s been created. Thank you to everyone who attended and for making the session a successful exercise, including Jonathan Lewis who started the ball rolling with the first question and some excellent comments and Tim Hall who managed to ask the first David Bowie related question 🙂

The heavy rain meant I didn’t have the patience or a strong enough umbrella to wander too far from the main Moscone complex, but I managed to catch a nice presentation by Karen Morton on how to effectively collect database statistics. She presented really well and I really it although perhaps didn’t highlight enough the perils of some of the auto statistics options, especially with regard to method_opt.

I then listened in to Dan Norris in the  OTN lounge on the new Exadata V2 offering. Certainly the columnar compression capabilities sound interesting. Of course I also heard that everything runs so fast that you might not need indexes on such a powerful beast, so perhaps my days on covering indexes on this blog are numbered 😉

I next had a look around at the other exhibition hall, practicing my golfing skills and picking up yet more t-shirts and yoyos that light up in funny ways. I’m a bit concerned that my luggage just won’t be able to hold all this stuff I’ve picked up !!

I have an interest in the Total Recall capabilities of 11g (and it’s lack of capabilities) and so attended a presentation on the improvements of Total Recall and flashback archive in 11g Rel 2. It looks like most of my issues with subsequent DDL changes on flashback archive enabled tables now being supported  one way or the other. However, I still have concerns with the potential “corruptability” of the archived historical data and the subsequent recoverability implications. It would also be a nice improvement if “who” made a particular change was more readily available without having to purchase yet more expensive database options or have to modify the table structure.

The final presentation of the day was Tom Kyte’s Top 11 new 11g Release 2 New features. His top 11 was basically:

– Do It Yourself Parallelism (with new dbms_parallel_execute feature)

– Analytics Functions (new ones such as LISTAGG and NTH_VALUE)

– Execute on a directory (and the preprocessor capabilities)

– Recursive Subquery Factory (self referencing WITH clause capabilities)

– Improved Time Travel (Total Recall improvements as mentioned above)

– You’ve got mail (new file watchers capabilities that can automatically invoke some code when a file arrives in a directory)

– Deferred Segment Creation (only allocated storage when the first row is inserted, not when segment is created)

– Flash Cache (write blocks back to disk AND an SSD like device so that subsequent reads from the SSD are faster)

– Parallel Improvements (such as better control of parallel process executions and memory parallel execution capabilities)

and both number 10 and 11 best feature, the killer one …

– Edition Based Redefinition (ability to have different versions of the same stored code running at the same time within the database)

As usual, Tom covered this topics with nice examples, in a very clear and concise manner.

On the way back to the hotel, I popped into the Blogger get-together function and had a few drinks and had the opportunity to meet and chat with a number of fellow Oracle bloggers. Thanks to the Alex Gorbachev and Justin and the OTN team for putting the event together.

PA140820

Aussie Oracle Bloggers, although one of us an Aussie no more 😉

It’s been a looong day …

Oracle OpenWorld 2009 – Day 2 Highlights October 14, 2009

Posted by Richard Foote in Oracle OpenWorld, Richard's Musings.
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It’s been a busy day today.

The effects of drinking perhaps one too many margaritas at the Oracle ACE dinner last night meant I was in desperate need of my morning coffee to start the day. Thank goodness for the OTN lounge 🙂

There were a number of announcements today but perhaps the main one from my perspective is the announcement of Oracle’s Enterprise Application Documents offering, an issue we’ve been battling for a long time.

I attended the Jonathan Lewis Unconference presentation on how to be an Oracle expert. It was all really quite interesting and raised a number of points that made one ponder. He asked for example what was the Oracle release that introduced the most significant change. See if you can come up with the same answer he gave (which after thinking about it is probably correct).

Later attended a general presentation that covered both 11g Release 2 and the new OLTP Database Machine Version 2. Usual marketing hype, much of which was already covered during the launch presentations. Discussed features such as RAC One, tiered storage partitioning options and advanced compression which are all certainly on my list of things to investigate.

Caught up with Gareth Llewellyn who mentioned the new OJAM Red Room website that has lots of Oracle  information and OpenWorld insights, with an Aussie / NZ emphasis.

After lunch, spent some time in the exhibition hall, stocking up on t-shirts, assorted pens and rubber ducks 🙂

Attended Jonathan Lewis’s other presentation on hints on hints. Again excellent, picking up a number of useful little tips, especially the full potential of the qb_name hint. I think he summarised things nicely when he recommended:

1) Don’t use them
2)  If you ignore recommendation 1, then be very very careful and precise when using hints

He also explained very nicely the myth that hints can be “ignored” by the CBO when he asked a poor soul from the audience to take off a jacket which he wasn’t wearing. He obviously didn’t perform what was asked of him as it wasn’t possible but did he actually ignore the request …

Later had a nice chat with Jonathan in the OTN lounge, exchanging thoughts mutual acquaintances we unfortunately know and the beauty and magic of Oxford City.

Finally attended the Battle of the DBAs Version 2 presentation which attempted to demo the potential productivity improvements when using the new EM capabilities and features. I don’t think they quite pulled it off but certainly highlighted that EM has some very nice features.

My mission tomorrow is to find out why they’re serving at the conference Seattle’s finest coffee here in San Francisco 🙂

PA130811

Oracle OpenWorld 2009 – So It Begins … October 12, 2009

Posted by Richard Foote in Oracle OpenWorld, Richard's Musings.
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Wow, I’ve had one hell of a 2 week period !!

I’ve been travelling around the southern part of England with my son, as part of  a school football tour, with 22 other teenage boys. It’s been a lot of fun but it’s also been extremely tiring, getting up early each morning, packing in as much as possible into each day, living in youth hostels with a room full of snorers, attempting to sleep on lumpy bunk beds, while making sure 20 odd teenagers don’t do what teenagers do naturally which is getting into trouble. On the whole we succeeded, losing just the one boy for just the one afternoon !!

Highlights included watching two English football matches (Tottenham vs. Burnley and the mighty Crystal Palace vs. Blackpool) and just walking around and enjoying the sights of wonderful places such as Oxford, Bath and London. Lowlight (other than losing that one boy for a while) was getting caught trying to sneak into a public toilet without paying the 50 pence fee only to be caught on CCTV and making the mistake of going into the ladies rather than the mens !!

Rather than go home and recover from the trip, I’ve now made my way across the Atlantic to enjoy Oracle OpenWorld here in foggy San Francisco.

Being a Sunday morning, it was a bit of a struggle and somewhat unnatural to get up early but Tom Kyte was doing the first keynote talk so I made the effort to attend. It was as usual with Tom an entertaining and interesting little discussion on what we as developers (and DBAs for that matter) still do oh so wrong. It covered topics such as how we often don’t know how to ask for help and ask questions properly anymore, how we try and make what should be simple as complex as possible (a real theme at my work at the moment), how we try to ignore and pretend mistakes never occur (don’t mention WHEN OTHERS SET NULL with Tom around), how we even fail to back things up properly and finished up on how best practices can often be abused and misinterpreted if we don’t fully understand the reasons and circumstances when something really is a best practice. All good stuff which is always worth reinforcing.

I had a little chat with Tom afterwards and found out to my joy that Tom is also a great fan of “Flight of the Concords” 🙂

I was then interviewed and filmed by Gareth Llewellyn and the gang from Australia Oracle Marketing on being at Openworld and the such and it all went rather well only to be told afterwards that they forgot to turn on the mike and would I mind being interviewed and asked the questions again !! I thought it was all so funny that I found it really hard not to giggle and laugh during take 2 of the interview. I’ll post the link once it gets uploaded to youtube or wherever. Here it is.

Later in the day I met up with a whole bunch of my Oracle mates, which of course is one of the main reasons for attending conferences such as this. One of them was Alex Gorbachev who also conducted a little interview with me 🙂 I think it’s going to be one of those conferences.

Tonight, I’m off  to attend the Oracle ACE dinner and catch up with more folk. If I don’t drink too much, I’ll try and answer some of the questions that have been slowly mounting while I’ve been away. Don’t like my chances though …

I’ll post a little list of highlights each day during the conference.