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UKOUG Oracle Conference agenda now out September 5, 2011

Posted by mwidlake in Meeting notes.
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I just wanted to drop a quick post to say that the agenda for the UKOUG annual conference is now out. You can check out the schedule here.

They seem to have dropped the TEBS (Technical and E-Buisiness Suite) out of the title, I think because last year the UKOUG staff kept getting asked if it was the annual Oracle conference they knew and loved from prior years. And of course it is. (Other “application” sides of the Oracle world, like JD Edwards and PeopleSoft, have their own dedicated, named UKOUG conferences).

There is also a return of the Sunday OakTable stream. For those who have not come across it before, it is a chance to see some presentations by members of the OakTable in a smaller and more accessible room. ie you feel better able to ask the presenters awkward questions :-).
I’m not sure of the exact details of registering for this part of the event but the agenda shows the talks that are happening (in fact, if you click on the “view the full 2011 agenda” icon on the agenda home page, it shows Sunday by default). I managed to get along to the OakTable Sunday a few years ago and loved it – I’ll be on the opposite side this time, I’m priviledged to have been asked to fill one of the slots.

As ever, the conference has a massive and wide-ranging agenda, with mini-streams like EXA(data/logic) and MySQL on Monday,APEX on Wednesday… The number of papers and the general quality that are submitted to the conference goes up and up each year and a lot of effort goes into not just picking well know speakers but also a mix of new presenters and ensuring topics get covered. It’s hard, but during the selection process sometimes there are 4 or 5 talks we know are going to be excellent but are all on the same or similar topic – some have to be dropped to ensure the breadth of topics is still covered. The number of slots a single person is allowed to have is also controlled, again to maintain space for a wide range of presenters and presentations. All in all, it is not a simple task and even now some tweaks are going on (to fill topic gaps, finalise the exact scope for a talk or to allow for people who suddenly find they cannot present anymore). You can rest assured though that, all in all, it will be an excellent conference.

Next presentations August 24, 2011

Posted by mwidlake in Meeting notes.
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I’ve got a couple of presentations coming up.

The first is at the UKOUG Management and Infrastructure SIG on Tuesday 20th September. I chair this SIG and it is all about how to manage Oracle when you have lots of databases, very big databases or a particular need to know a bit more about the rest of the IT Infrastructure. You can find the schedule here. The aim is to talk at a technical level but not the deep-dive of some of the RDBMS or HA presentations as we want to cover a wider brief.

As I say, one thing we do is look at the hardware your Oracle databases and application servers need to run on. This meeting we have Steve Shaw from Intel talking about getting the most out of your Xeon-based servers, but the general concepts apply to other platforms. If you are old enough, you will remember how you used to set up “HIMEM.SYS”, “EMM386.SYS and try to keep as much of the first 640K of your memory free. You might even have got down and dirty with you BIOS settings. We did it as the performance boosts were significant. Well, we don’t do that sort of thing anymore and Steve’s talk will probably make you want to! It still is a free way to get more out of your hardware.

Piet de Visser is also coming along and I always really enjoy his presentations. This time he is covering something of interest/concern to many of us – Outsourcing. I think that will be a pretty lively session.

I’m presenting as well, with Neil Chandler on the topic of how deep you should dive when solving technical issues. To 10046 trace or not.

We meet in Oracle’s city office, so handy for anyone in or around London or for anyone coming in from North of London (the office is 5 minutes walk from Liverpool Street Station and three stops along the underground from King’s Cross St Pancras). We’ve still got to finalise one or two agenda slots but they will be real-world talks about Enterprise Manager/GRID control. One fixed item on the agenda is that those who wish to retire to a pub afterwards to continue the discussions.

You may have noticed the little logo for the UKOUG TEBS conference appearing at the right of this blog. The agenda is not quite public yet so I cannot say too much, but I will be presenting at the event, on Index Organized Tables. I’ll be showing demonstrations of some of the things I have been blogging about and expanding on areas, joining it all up into one session. I might also be presenting on database design but that talk is being discussed and finalised at present. The UKOUG team have a lot of things that they have to pull together and organise just for the presentations, never mind the rest of the conferences such as the exhibition hall, catering, registration etc. I’ve been involved in helping with the agenda organisation this year, in a minor way, so I’ve seen it all from the inside.

The TEBS conference is, for me, the meeting highlight of the year. I’ve been to Oracle Open World and, interesting though it is and with some fabulous presentations and events, it is just too big, corporate and company line for me. Oh, I’d go again when the opportunity arises, but for me the UKOUG TEBS conference has a much better feel to it, you still get a load of great talks from Oracle about the latest/greatest, but you also get loads and loads of talks by many of the best in the field and the talks are independent – no pressure to be upbeat about Oracle or avoid any negative messages. In fact, if you honestly feel something in Oracle is worth avoiding, you are free to present and say “Don’t Do This!” :-)

I had planned to go to more of the European conferences this year but it did not get myself organised. For me, as an Independent consultant, I need to present to justify the trip and I keep failing to get the submissions in on time.

Telling the Truth in IT March 17, 2011

Posted by mwidlake in Meeting notes.
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I’ve been doing presentations for many years, mostly on Oracle Technology, occasionally on management topics. However, my favorite presentation to give is one about when things go wrong.

The title is usually something like “Surviving Survivable Disasters” or “5 ways to Seriously Screw up a Project” and, though the specific examples and flow may vary, the general content is the same. I talk about IT situations that have gone wrong or things that strike me as daft/silly/mindless in IT. My aim is to be entertaining and have a laugh at the situations but I also want to explore what causes disasters and how we might go about avoiding at least some of them.

When doing the presentation I have a couple of ground rules:

  • I must have witnessed the situation myself or know personally, and trust, the individual who is my source.
  • I do not name organisations or individuals unless I am specifically given permission {by individuals that is, organisations never get named. Except one}.
  • I try to resist the temptation to embellish. It’s not hard to resists, a good disaster usually stands on it’s own merits.

It’s a great talk for introducing some light relief into a series of very technical presentations or for opening up a day of talks, to get people relaxed. It’s also the only talk I get seriously nervous about doing – if you are aiming to be entertaining and you miss, you stand to die on stage. The first time I did the talk I was physically sweating. However, it went down a storm. I did it 4 or 5 more times over as many years and it always went down well.

However, about 4 years ago I did the presentation just as I was about to go back to being self employed. After the talk a very good friend came over and said something like “Really entertaining talk but…maybe you should tone it down? A lot. Potential employers are going to take a dim view of you doing this, they will worry they will appear in the next talk”. I protested that I never mention companies or people and, surely, all organisations are able to admit that things go wrong and it is to everyone’s benefit if we all learn from them? My friend was adamant that though companies want to benefit from other disasters, they never, ever want to in any way be the source of that benefit. He was sure it would be very damaging to my potential career. Hmmmm…. I could see his point.

I was already scheduled to do the talk again in a couple of months and I took heed of his advice for it. I toned down the material, I removed some of the best stories and I added several disclaimers. I also died on stage. It went from an amusing 45 minutes to a preachy and stodgy affair.

I have not done it since.

The question is, should I have pulled back from doing that talk? Is it really going to harm my potential employability? (After all, no work has ever come my way from presenting). Why can’t we be honest that issues occur and that learning from them is far more valuable than covering them up? After all, do we believe a person who claims never to have made mistakes?

What prompted this thread is that I have been asked to do the talk again – and I have agreed to do so. I’ll be doing it next week, with the title “5 ways to advance your career through IT Disasters” for the UK Oracle user group Back to Basics event. This is a day of introductory talks for people who are fairly new to Oracle, the brain-child of Lisa Dobson. Lisa realised a few years ago that there were not enough intro-type presentations, most technical talks are by experts for fellow experts {or, at least, people wanting to become experts}.

I’m very happy to support helping those who are new to Oracle and I think it is important that people who are new to IT are exposed to what can go wrong – and any advice that might help them avoid it. After all, it’s better they learn from our mistakes than just repeat them again. OK, they’ll just repeat them again anyway, but they might spot that they are doing so just in time :-)

Is this a good idea? What the hell, I want more free time to do things like this blog – and get on top of the garden.

How NOT to present November 30, 2010

Posted by mwidlake in Meeting notes.
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I’m at the UKOUOG this week and, as ever, the presentations vary in quality. Most are excellent {or even better than that}, some are not. I was in one first thing this morning and, I have to say, it was rushed, garbled, unclear and there was a definite air of unease and panic. I’m not even sure the guy got to his big point and I could think of at least three major things he did not mention at all.

I think his main problem was just starting off in a rush and never settling down. You see, I was stuck on the top floor of my Hotel and had to run to the venue. Yes, the poor presentation was by me :-(.

I usually present well {modesty forbids me from saying I am a very good presenter – but modesty can take a hike, my ego knows I am capable of giving great presentations}. I am one of those lucky people for whom presenting has never been particularly frightening and, in fact, I find it easier to present to a group of people than talk with them.

But not today. I was already worried about the session, have been for weeks, as I was doing interactive demos. But last night I ran through it, wrote down the names of the scripts and the slide numbers so I could just bang through them and timed it all. 50 mins, I would skip one unneeded section. Calm. I got a reasonable night’s sleep, got up early and ran through it all one more time, making sure my Big Point demo worked. And it did. Yes.

Went down to breakfast, had breakfast and back to the room to pick up my stuff. And realised I was late. Less than 10 minutes to do the 5 minutes over to the venue. So I fled the room, stuffing my laptop in my bag. But not my notes. Or my conference pass. I did not think of this as I stood on the top floor of the hotel, I just thought “where are the lifts?”. They were all below me, ferrying hungry people to and from breakfast. After what seemed like an hour and was only 4 or 5 minutes I decided 16 flights of stairs was OK to go down and, to give me credit, I managed those stairs and the few hundred yards to the venue in pretty good time. I did pause for a few seconds at floor 7, I think, when I remembered my notes. Too late.

But I was now panicked and arrived as a dash. I had to mess about with the Audio Visual guy to get going and started 2 mins past my slot start – and then did the 5 minutes of non-relevant stuff I had decided to drop. It was game over from there, I was failing to find the correct scripts, I was skipping relevant sections and I was blathering instead of just taking a few seconds to calm down and concentrate.

Oh well, my first time in a large room at the UKOUG and I messed up. At least I had the key lesson drummed into me. TURN UP EARLY!!!!

Advert – UKOUG conference, end of November October 30, 2010

Posted by mwidlake in Meeting notes.
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The best Oracle event in the calendar (in my opinion) is only a month away now. From Monday 30th November to Wednesday 1st December the UK Oracle User group Technical and E-Business Suite (TEBS) conference is running. {Being old-school I still think of it as the UKOUG conference but the user group also run other conferences for eg Siebel, Peoplesoft and the up-coming JD Edwards event, dedicated to those segments of the constantly growing world of Oracle}.

I love the TEBS conference. I loved it when I knew almost nobody else attending it because of the breadth and quality of the technical presentations. When I was a manager I liked the fact I could mix going to the technical stuff to going around the demo booths and seeing if any of the services on offer were of interest. And now that I know more people who attend the event, I love catching up with them and also meeting new people who maybe I only knew before by name or reputation.

The social events around the conference are no where near in the same league as those at Oracle Open World – which means that the UKOUG ones are not massive and unfeeling, but of a size where you can bump into friends and be introduced to other people. {And, I should add, the UKOUG staff do an excellent job of organising them}. I’d say half the people I know in the Oracle world I met at the conference.

So having said how much I like the conference, the question is, am I presenting this year? There seems to be an inverse relationship to the number of years I have been attending and the number of talks I do. Back in 2004 I did 3, in 2005 and 06 it was 2, 2007 was 1. 2008 I had to skip the event and last year all my proposed talks were rejected. I blame the fact that the quality and number of abstracts submitted goes up each year.

The good news (or bad news, depending on your opinion) is that I am presenting again this year, first thing on Tuesday at 08:45

My SQL is suddenly performing badly and nothing has changed. Why?

I’m actually very nervous about this presentation as I want to not only describe why SQL might change how well it performs but also demonstrate the reasons – and how you detect them. Demonstrations take an age to prepare and, as fellow presenters know, have this nasty habit of dying under your feet. I’ve not got a lot of spare time at present so I already feel I am behind schedule!

I’ll also be curious how many people from the MySQL field drift into the room thinking it is part of the MySQL stream {which runs on the Wednesday}. Sadly the talk will be of no use at all to them as it is very specific to Oracle!

Despite the presenting duties, I’m really looking forward to the event. I’d love to meet anyone who reads my blog, whether you like it or not. Just stop me and say “hi” if you see me around.

Advert – MI SIG on 5th October September 13, 2010

Posted by mwidlake in Meeting notes.
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The next UK Oracle User Group (UKOUG) Management and Infrastructure SIG is coming up in a few weeks – 5th October in the Oracle City Office. You can find the latest agenda here. If you do not know what we (the MI SIG) cover, it is basically technical topics at a slightly broader level. So not so much example code but how feature X works or how to use Y over 100 databases plus. We also touch on management issues, which I always worry will put some potential attendees of,f but in fact nearly always goes down very well.

We have an excellent line up of topics and presenters for this meeting. Does Exadata work in the real world? Peter Scott will be presenting some of what he has learned doing this. Want to know about oracle’s latest licensing options and how to save money? Alex Sandercock from Turnstone Services will be talking about that. Confused about how storage is changing and how the database interacts with it? James Moorle will cover that one.

It has been a real struggle getting the agenda together for this meeting, I can’t believe we have ended up with such a strong one in the end. I mean, I am not even having to bore everyone with my voice again.

The first problem was I just failed to get the organising started. As the Chair, it is my main function to sort out the meetings. It was always “tomorrow” as I had so much on for every “today”.

The second problem was we were up against Oracle Open World. We had a few people “in hand” who had indicated they would be happy to do a talk for us, but were scheduled to do OOW. I thought it was a bit mean to turn us down for some obscure vendor event in the US. So we moved our event by a month.

The final problem was that we still had trouble with speaker availability, as it was now so close (it might not seem close if you are considering going to a meeting, but if you are being asked to sign up to preparing and giving a presentation, 5 weeks is not a lot of notice).

It all came together in the end, with the help of the co-chairs, especially Neil Chandler.

I know I have said this before, but I struggle to understand why SIG meetings are not flooded with people coming to them. It is free training in effect (if your organisation is a member of the UKOUG – £80 otherwise, I think). All the presenters are experts, often presenting similar talks to those given at Oracle Open World or the UKOUG Conference. OK, it is a day not working in the office but as well as the “free training” you meet up with other people who have similar work issues as you. I find it invaluable to have a circle of external people I can occasionally say “What do you think of this” to. The meeting other people is aided by us retiring to a pub after the event, for those inclined to do so.

I try to get to SIGs when I can and in fact, if I was not at my own on the 5th, I’d like to be at the modelling and architecture one – I’ve been meaning to get to that one for ages.

Friday Philosophy – The Science of Oracle June 11, 2010

Posted by mwidlake in Friday Philosophy, Meeting notes.
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The title to this blog is very misleading. It is not about scientifically understanding how Oracle technologies work or even about the technology itself.

It is actually about the fact that a lot of scientific organisations, both academic and commercial, work with Oracle technology in ways to do directly with the science {as opposed to using it for CRM, HR or tracking students and results, which they also do but I’m not interested in that}.

If you have worked in Academia or charitable scientific organisations it can be a little suprising that Oracle is used so much, as it is expensive and corporate – there is a tendency to be poor and anti-corporate in such environments. But the thing is, Oracle is able to handle large amounts of complex data, in many formats, in many ways, and most programming languages can easily access the data in the database. You can achieve a lot with just PL/SQL and Java of course.

Commercial scientific organisations, like large Pharmaceuticals, use it for the same reasons of course, but for them the cost is not such an issues {I can imagine IT managers in such organisations going “It damn well IS an issue!” but trust me, not in the same critical way}.

What is the point of this blog? Well, it’s about user communities. The scientific community have a tendency to push the Oracle database further than most Oracle users do. Take data volumes. I worked for many years for the UK-side of the Human Genome Project and part of what I did was create an Oracle database that scaled to 100TB. Even now that is pretty large but I was designing and implementing it back in 2004-2005. The data volumes CERN are going to have to handle for the Large Hadron Collider just dwarf that, and they only hold summarised data of summaries of the actual raw scientific data generated.

Another aspect is coping with very rapid change, for example systems to support lab processes. This is similar to your standard factory management system except that the level of change can be daunting. The process can change, well, weekly, as the science and techniques improve in the lab. Those scientist might even completely change what they are doing when some unexpected avenue opens up. I say “might”, seemed to happen every month.

In scientific organisations there tends to be more openness about what and how they do things. Academic and charitable scientific organisations tend to put less barriers in the way of exchanging knowledge than corporations do and so that encourages more exchange of information. When I was working in the area I was positively encouraged to go to conferences and present. Obviously this is not always true and scientific corporations, like Pharmaceuticals, have gained {rightly or wrongly} a reputation for being very reticent about sharing any knowledge at all. But often the individuals involved will share.

So, the scientific community push areas of the technology very hard, they tend to be an open bunch of people, cost is often critical and, the final thing I have not mentioned, is that they often speak a language only vaguely recognisable as English, due to the jargon. Sounds like a community to me.

The real reason I mention all this is that it looks like, after about 4 years of considering and discussing having a science SIG {Special Interest Group} in the UKOUG, I will finally be putting together an agenda for an initial meeting for such a thing. I wonder if it will be a success?

Northern Server Technology Day – Advert April 22, 2010

Posted by mwidlake in Meeting notes.
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I’m a bit late doing this, but next week is the UKOUG Northern Server Technology Day.
As the title suggests, this is a day of technical presentations for Oracle users in the North of England. Of course, it is open to any UKOUG member (and anyone else, for a small fee), but the idea behind it is to provide a user group event for those who are not based in the South of England and so might struggle to the usual events. This year the day is being held in Leeds, which is where I was at college, so I am more than happy to return to my old stomping ground and support the day with a presentation on Database Statistics.

There are other, probably much better, presentations by David Kurtz, John Hallas, John Scott, Piet de Visser and David Phizacklea too. I’ve seen them all do their stuff before and it should be a cracking day. Check out the agenda via the link at the top of this post.

If you are an Oracle user who is based up in the North and have an interest in the meeting, I would urge you to make the extra effort to attend. It is a constant complaint that the UKOUG is biased towards having events in Reading, London and the Midlands and not a lot elsewhere, but to have events further afield there needs to be an active and interested audience to justify the event. The better the event is supported, the more likely it is to continue and prosper and potentially attract other UKOUG SIG meetings North.

Actually, on that note, I will also mention the Scotland 2010 conference meeting, a must for Oracle users in Scotland or those who would like to mix a technical conference with visiting Scotland {and I have to say, I do enjoy visiting Scotland}. Not sure yet if I can get there myself this year :-(

Advert for the Management and Infrastructure SIG March 24, 2010

Posted by mwidlake in Management, Meeting notes.
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I’m a bit late doing this (life is just too busy at the moment) but I want to mention the next Management and Infrastructure Special Interest Group meeting of the UKOUG next Week. Tuesday 30th, being held in Oracle’s London City office.

I get asked by people what exactly the MI SIG is? {Honest, I do, I got asked twice this month alone!}. Is it a management meeting or is it another one of the technical SIGs, like the UNIX, RDBMS and RAC/HA SIGs? I’ve struggled to come up with a single line to sum it up. Other than to say “Both”.

It might be easier to sum up the target audience. The MI SIG is for technical people who need to deal with Oracle as a component of a large IT environment. Most of the audience could knock up a PL/SQL script to create a new set of tablespaces each month, would be able to instal Oracle {if given a couple of days and the manuals to peek at} and could explain two-phase commit. Maybe.
But what they have to deal with in their working lives are things like using Grid Control to manage 500 instances, understand what options are there for providing disaster recovery {if not the exact commands to eg set up physical standby or active/passive RAC}, knowing enough about storage options to make a sensible decision on which is best for each type of Oracle system they have. So it is a technical SIG, but covering general principles and, well, Infrastructure.

And the Management? Well, when the SIG started this bit was really interesting to me. When you have a lot of IT going on, especially in large organisations, the people looking after Oracle are not the people looking after Networks, or Storage, or Backups or half a dozen other things. And you probably have a team of people doing all that Oracle stuff with/for you. So you have to hire staff and keep ‘em happy and deal with teams who you have no power over but you need them to do stuff for you. And that Management part can be a lot harder than the technology, especially if you never planned on being a manager but just woke up one day with that monkey on your back.

So with the technical aspects of Large IT Infrastructure comes the management component too. The SIG is there for that audience.

I chair this SIG, so I am more than a little bit biased, but I think it is a good line-up of talks for this up-coming meeting. We have two talks on using OEM/Grid Control, one around using it for deploying clusters, one about how you go about integrating it with the likes of LDAP, Kerbros and using the Custom Metrics, ie plugging it into the wider infrastructure.

We also have a presentation on the latest/greatest Exadata2, from some Oracle friends.

To wrap up the technical talks I am going to try and explain some of the guiding principles for gathering statistics for you oracle databases. Not the details of DBMS_STATS command syntax, but why you need good stats, how you get them and the issues we all seem to end up facing with it.

Balancing the techical side is a talk on Birkman and understanding teams and people.

So, you can see it is a line-up matching the diversity of the SIG’s purpose.

As I said earlier, I initially was very interested in the management side of the SIG and I worried I would be pretty lonely in that opinion. For various reasons, those of us on the technical side tend not to have much time for those “soft skills” we associate with management theory. However, when I took over the SIG over a year ago, I asked the audience if they would want some talks on hiring staff, dealing with people, motivation… Over 60% of the audience said “YES!”. Quite loudly. About 30% said “OK, so long as we get technical stuff as well”. 6% said “over my dead body”.

I think the reason so many wanted the management side as well is, whether we like it or have an affinity for it or not, it is part of the job. And so we need to be able to do it. Personally, I quite like the human side of IT, but my wife tells me I am strange.

If your organisation has UKOUG membership it is free to come along to the SIG (one person per membership, excluding Bronze membership) Anyone can come along for £80. You would be very welcome and I am sure you will learn new stuff. Don’t let the fact that we retire to a pub afterwards where the chair buys a round sway your decision to come along at all.

DBMS SIG March 10, 2010

Posted by mwidlake in internals, Meeting notes, performance.
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I went to the DBMS SIG today {DBMS Special Interest Group meeting of the UK Oracle User Group}. Don’t worry, I am not going to run through the set of presentations and make comments on them – although I like reading such entries by others on their blogs, I generally like them due to the style of writing as opposed to getting information out of them. But there is the odd tidbit that can be worth disseminating to as wide an audience as possible and I like to do my bit.

Having said I won’t go through all the talks… :-). No, I just want to comment that all the talks had merit at this meeting and, quite rightly, the meeting was full. This is nice to see as last year SIG attendance fell across the board, due to the “economic climate”. Very daft, in my opinion, as I see SIGs as free training plus networking opportunities (sorry to use the “networking” word” plus different viewpoints, all of which are invaluable at any time and especially valuable when things are hard.

Go to SIGs (or whatever is available in your country) as it is always worth the day invested. Where else can you see half a dozen experts give opinions and also corner them and ask them more stuff as well?

Anyway, the tidbits. First, Jonathan Lewis demonstrated how he goes about solving issues with complex SQL statements. It was terribly feindish and extremly clever and needs incredible in-depth knowledge of the oracle RDBMS… He draws a pseudo Entity Relationship Diagram of the tables involved, adds in some figures on what filtering will achieve and what ratio of records will be involved in table joins and asks the question “what will probably happen” a couple of dozen times. Yes, I lied, it does not need vast knowledge. It needs a clear, simple approach to solving the problem. And an ERD. I love ERDs and rue their general demise. I use exactly the same method myself to investigate complex SQL performance issues {I think I could be accused of trying to ride on shirt-tails here, but honestly, the step I take if an Explain Plan does not help me is to ERD the statement and look at the indexes and ratios between tables to see how I , as a human, would solve the query. Chatting to a few other old lags, it is a relatively universal approach by those of us who have used ERDs}. If you are a member of the UKOUG I strongly recommend downloading the slides to Jonathan’s talk. If you are not a member, maybe Jonathan will present it again at another venue, or you could get him to come along and do a course on tuning. {Jonathan, if you get a gig as a result if this, I want a pint of Marston’s Pedigree, OK?}

{And thanks to Sean malloy for commenting to provide a link to a published version of Jonathan’s method – Jonathan did mention this, highlighting the fact that it is his first real foray into SQL*Server. However, the method is database agnostic. This is the article}

Second tidbit. Adrian Dodman and Owen Ireland (who both look remarkably like Hollywood hearthrobs in their pictures, but different as their in-the-flesh selves, though very decent chaps they are too.) did an excellent talk on VLDB physical standbys, a topic that has particular resonance for myself. They mentioned parallel_execution_message_size. This defaults to 2k, on 10g at least. It is a rubbish setting. No, let me not beat about the bush, it is an utterly rubbish setting. If you use parallel query, parallel recovery or parallel anything-at-all, check out this parameter and, due dilligence allowing, increase it. Try 8k as opposed to 2k and even 16k. The manual on it says the default of 2k/4k is fine. It ain’t. Increasing the value just takes some memory out of the shared pool and, these days, if you can’t afford a few extra KB out of your shared pool, you need to replace your server with something costing about twice as much as a top-end desktop PC. { Why am I so vigorous in my opinion on this parameter? Well, I had a situation a few months back of trying to migrate a database to a new geographic location for a client in Germany. We did a backup/recovery type operation to do this. Applying the redo logs was proving to be a performance issue so Oracle Corp suggested parallel redo log application. It ran a LOT slower than single thread, about 300% slower. However, increasing the parallel_execution_message_size from 2k to 8k made the parallel log application about 400% faster than single thread. ie a dozen times faster. I know from presentations by Christian Antognini and discussions with others that it is a key parameter to getting parallel query to perform well too.}

Last tidbit. Don’t drop the OUTLN user. Yes, I know, why would you? Just don’t, OK? Especially on Oracle 11. If you do, for whatever reason, DO NOT SHUT DOWN THE DATABASE. Call Oracle Support and pray. Thanks go to Peter Mahaffey for that one. Yes he did. It all went terribly wrong for him.

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