Boneist's Oracle Blog

After a late night (um, < 4 hours sleep...) I was up bright and... well, just early now I come to think of it! I checked out, retrieved the coat (phew!) I hadn't realised I'd left in the hotel bar until just before I was about to leave the hotel room for the final time and had breakfast. Then it was off to the first presentation of the day... Statistics On Partitioned Objects – Doug Burns

I have a feeling that I’ve seen this presentation before – it’s possible that I haven’t seen the entire presentation, but I believe Doug did a couple of work presentations around this subject. Anyway, whether it was those or his blog entries on the subject, a lot of it felt familiar. Doug is an engaging speaker, and the subject is an interesting one. I’m not sure whether it’s applicable to the way our databases are designed, but I will be recalling this talk (amongst others) when I think of ways to improve our stats gathering when we go to 11g.

Using GoldenGate To Minimize Database Upgrade Risk – Marc Fielding

I didn’t fully understand what this talk was going to be about when I signed up for it, but having just worked with and upgraded GoldenGate following a bug in the version we use, plus the upcoming 11g upgrade, I thought it would be a good thing to go to.

Ultimately, I don’t think it’s applicable in our situation this time, but it was about using GoldenGate to copy the data changes from a, for example, 10g database up to the same db but in 11g. Potentially very useful, so a good idea to have in the back of my mind, should I ever come across a situation where it could be used.

The talk was aimed more at DBAs than devs, I think, but I was pleased that I understood most of the GG terms he used – our recent issues at least consolidated my GG knowledge, so it wasn’t all bad!

Optimizer Statistics – A Fresh Approach – Connor McDonald

Yes, the keener eyed/memoried amongst you will spot that I attended this on Sunday. Well, I did have another session lined up to go to, but by this time, my brain couldn’t handle much! Connor was just as amazing as he was on Sunday (no surprise there, then!), and I was able to just sit back and be entertained! (Thanks Connor!)

Faster, Leaner, More Efficient Databases – Index Organised Tables – Martin Widlake

Martin has done a series of blog entries on IOTs and this proved to be an interesting talk. I’ve used IOTs in the past, and will perhaps again, now that our version of GG has gone up to the latest version (the version we had previously couldn’t handle IOTs; I’m not sure about the new version, but I’d hope it would!).

The performance stuff was especially interesting, so I’ll have to go away and see how it might be applied in our databases. A good talk to have gone to.

What Shape Is Your Data? – Niall Litchfield

This was the last talk of the conference, and it was interesting. Niall took us through some examples of how data might be organised and what can be done to best optimize it.

Truth be told, I was flagging a little by this point, so didn’t retain as much of the talk as I’d have liked – I’ll definitely be downloading the slides, when they appear!!

So, Tuesday dawned bright and … er, well I didn’t go in for the first session of the day (not that I’d found one I wanted to go in for anyway, so nothing lost there!) but I was definitely there for the second session!

Who’s Afraid Of Analytic Functions? – Alex Nuijten

Alex is someone I’ve known from the OTN SQL & PL/SQL forum for quite some time now, although I’ve only met him in person a couple of times now. He’s a massive proponent of analytic functions (as am I – seriously, they *rock*!) and I couldn’t miss his analytics talk. Sorry Niall – I would have loved to have gone to yours too, but this just pipped yours!

This was one of the few that I came out of thinking that maybe I wasn’t actually so dumb after all! As with everything, there are lots of ways of doing the same thing, and although I’m fairly comfortable with analytic functions, there are still ways that I approach things that aren’t the most efficient. Some of Alex’s examples highlighted that for me!

If you aren’t familiar or comfortable with analytic functions yet, I would highly recommend you go see one of Alex’s talks on the subject!

A Year In Purgatory – Diary Of An 11.2 Upgrade – Connor McDonald

This was a presentation that very nearly wasn’t given! Debra Lilley had seen it when Connor did it in Perth, and was determined to get him to do it at UKOUG. Given that he’d already used up both slots for other presentations, this one was going to be saved for next year but, due to someone else having to pull out at the last minute, Debra got her wish!

All I can say about this is poor, poor Connor and his team (I assume there was a team?!). He took us through all the mishaps that occured in the past year or so when upgrading to an 11g Rac environment. As per his normal presentation style there was plenty of humour and entertainment, but I’m amazed that he’s got any hair left after the nightmare he described!

Troubleshooting The Most Complex Oracle Performance Problem I’ve Ever Seen – Tanel Poder

This was an intersting talk in that for most of it, I was scratching my head as to why it was an Oracle problem! It turned out to be a problem that Doug Burns had encountered (sorry, no spoilers here!), and whilst I basically followed things, I think it was more aimed at a DBA than someone like me. Still, it’s interesting to pick up little tips and tricks on the O/S side of things. And of course, the more I know about the underneath areas of Oracle, the easier it is to talk to my DBAs!

It’s All In The Index – Michael Salt

Poor Michael only just made his presentation, by the sounds of it – massive train problems! However, he made it and produced a useful talk on indexes and how they can be used to improve the performance of poorly running SQL statements.

I didn’t always agree with what Michael said (add an index to aid queries on tables where the data is stored in the wrong datatype? Fix the table/data, not mitigate the symptoms! Meanwhile, back in the real world, I know that’s not always possible!), but he did throw up an interesting off-the-cuff remark that completely stopped me in my tracks! I’ll be blogging on this shortly!

Beating The Oracle Optimizer – Jonathan Lewis

This was a tour of how to optimise a two-table query in 7 different ways – some of which I would never have come up with in a million years! An excellent presentation, as always.

This also happened to be the one that Jonathan asked me to be his alarm clock! I was so worried about missing the 10min / 5min warnings that he’d requested, I was checking the time every other minute or so throughout his presentation… only for him to finish 3 minutes before I was due to give him his 10 minute warning! By this time, I was panicking that the time on both my watch and my mobile phone was wrong or something, whereas Jonathan had apparently been thinking that I’d be waving at him any second for quite a while! Hehehe; I got all worked up for no reason!

Challenges And Chances Of The 11g Query Optimizer – Christian Antognini

This was a bit of a whistlestop tour through the 11g Query Optimizer changes and what we could expect to see once we’ve upgraded to 11g. Some of these I’d already seen covered in earlier presentations, such as SQL Plan Management, but others I was completely unaware of! A useful session to go to if, like me, you’re contemplating upgrading to 11g.

Opening Keynote – Mark Sunday

Before Mark came on, we had Debra Lilley and Lisa Dobson give a short talk about the changes in structure in the UKOUG organisation, which was interesting – I wasn’t aware that there’d been such big changes.

Mark came on and gave a talk about how fab Oracle was, and … well, that was my take-home message *{;-) I suspect I may not have been part of the ideal target audience!

SQL Tuning – Kyle Hailey

I’ve seen a couple of presentations in previous UKOUG conferences that were similar to what Kyle presented here – one by Jonathan Lewis on diagraming SQL statements and one by Wolfgang Breitling on tuning sql by cardinality. What I particularly liked about this one is that Kyle used a program to do the diagramming – it can be done by hand, but boy, do I now want that program! I’ll have to research it and see if I can navigate my work’s purchasing maze to get it, assuming we don’t already have it!

I also need to get Dan Tow’s book, which Kyle had based his talk upon.

Partitioning 101 – Connor McDonald

Yes, another entertaining Connor show! This time, all about partitions. I knew most of the pre-11g stuff, but not too much about the new 11g features (I’d heard about the new Interval partions, but not the rest). Connor took us through the different types of partitions and gotchas, tips etc. I shall definitely be revisiting partitions when we go to 11g!

Oracle Optimizer – Upgrading to Oracle Database 11g Without Pain – Maria Colgan The Optimizer Lady

Maria took us through the steps required to successfully upgrade to 11g with minimal pain due to the optimizer changes. A lot of this revolved around SQL Plan Baselines, which sound useful, but I’m not sure I fully “got” it, or how it could apply in our 11g migrations. Yet more things I’ll be adding into the “Things To Consider” pile for our migration!

With all the steps Maria was covering, I was beginning to panic about our migration, until right at the very end, someone asked a question of the rest of the audience: “Has anyone had a bad upgrade to 11g?” which got a tumbleweed! Someone replied and said it had gone smoothly for them, and another response was that they’d not heard of a bad upgrade, so that somehwat put my mind at rest!

Database I/O Performance Measuring and Planning – Alex Gorbachev

I suspect this was aimed mostly towards DBAs, but it sounded interesting, so I thought I’d go along anyway. Some of the technicalities went over my head, but it was useful – I can at least raise the discussion of I/O capacity planning with my DBAs and at least have some vague understanding of what I’m talking about! *{:-)

Performance and Stability with Oracle 11g SQL Plan Management – Doug Burns

Doug went into SQL Plan Management a bit more in depth than Maria – whom he insisted on calling “The Optimizer Lady” throughout his talk! – did, but it wasn’t too indepth, which was perfect for the time of day (being the last presentation before the final keynote of the (very long and full) day, and also served as excellent consolidation for Maria’s earlier presentation.

First, a note about how I’m going to write up this year’s UKOUG Conference. There was a looooot happening this conference, both socially and learning-wise, so I’m going to break things up – first, I’ll write up my thoughts on the presentations (over several blog entries!) and then I’ll write up my networking/social/fun thoughts.

So anyway, this year, UKOUG and the Oak Table guys got together and put on an extra day’s worth of sessions (which were repeated later on in the conference). Despite National Express East Anglia/Network Rail’s best efforts (Cambridge train station was closed!) I managed to get to Birmingham in time for the start of OakTable Sunday – mainly due to the fact that my other half very kindly drove me to Milton Keynes so that I could catch the train from there! This had the bonus side effect of me not having to get up early enough to catch the coach from Cambridge station at 5:50am!

Anyway, on with the presentation write-ups:

Tales From The OakTable – Mogens Nørgaard

I’ve never seen Mogens before, though I’ve heard plenty about him, and it was somewhat of a shock! He was incredibly laid back, and started off by saying that we were probably not going to learn anything over the conference, or at most, about 5% would stick with us after the conference.

He treated us to a few stories about the OakTable and its members, encouraging stories from Oakies in the audience too. I wasn’t quite sure what to make of this, really, as it was a very strange talk! Perhaps if I’d seen Mogens present before, then it wouldn’t have been a surprise!

About Multiblock Reads – Frits Hoogland

This was about the changes to multiblock reads in 11g, and how you cannot rely on scattered reads anymore – sometimes it will choose to do direct path reads, which means that you lose the advantages of query results being cached. This could be a good thing or not, but it was something I was unaware of (even though Doug has apparently already blogged about it!). Given that we will hopefully be migrating our 10g databases to 11g next year, I’m very glad I went to this session!

Optimizer Statistics – A Fresh Approach – Connor McDonald

Having seen Connor present at the 2009 UKOUG conference, I was determined that I was going to see as many of his presentations as I could. Thankfully, he presents on topics that are relevant to me, but even if he didn’t, I’d go along and see him in action! Honestly, if you’ve never seen him present, if you should ever get the chance to do so, do! He is *a* *maze* *ing!

Connor talked about statisics, both object and database stats, such as how you should gather stats, etc. There were some ideas in there that I’d never considered before (pending stats), but I’ll definitely go back to work and think about our stats strategies etc!

Statistics Gathering and Histograms – DOs and DON’Ts – Wolfgang Breitling

Following on from Connor’s presentation was Wolfgang’s. He went into more detail on histograms and was of the same opinion as Connor – don’t use histograms if you don’t need to; set them explicitly. Another talk I shall consider when looking at our stats gathering!

Performance and High Availablility Panel Session

Finally, the OakTable Sunday was topped off by a panel session of various OakTable members who took questions from the audience and wanted to know about the longest prod outage that people were brave enough to own up to! Thankfully, I’ve never caused a prod outage, but someone had had an overnight outage and someone else had had 18 hours although I don’t think it was caused by them. Connor won on the monetary outage front – he managed to hose a 10 million Aussie dollar truck through a bit of dodgy code!