Friday, November 30, 2007

UKOUG 2007: My schedule

Although it's nice to go to both OpenWorld and the UKOUG conference it is difficult when they're both so close together. I haven't finished digesting the stuff from OOW2K7 yet. Also being part of the UKOUG committee means I have a few light pre-conference chores. Furthermore, I'm presenting, so there's all that to prepare. Plus the small matter of the day job, which doesn't really respond well to two separate absences so close together; that's why I'm not doing the full UKOUG this year (again). Anyway, enough whinging.

My standard take on the two conferences is that OpenWorld is more fun but you learn more at the UKOUG. This is because OpenWorld is usually dominated by Oracle's marketing and placed presentations (there is no open Call For Papers). The UKOUG is independent of Oracle and casts its net wider. Consequently you generally get a better range of speakers and topics, and a more honest appraisal of Oracle's products. However, OpenWorld07 was a valuable learning experience for me and - compared to previous years - quite low key in the hype department. So the UKOUG Conference has a tougher challenge this year.

One thing I do know is Birmingham in December will not be T-Shirt weather.




For those of us on the committee the conference starts at 16:15 on Sunday with the Volunteers' meeting. Followed by a few sherbets at a local watering-hole.

Monday, 3rd December 2007


12:10-13:10 - "Avoiding Avoidable Disasters and Surviving Survivable Ones" : Hall Exec 8

I felt like easing myself into the conference, so I chose my first session for its potential entertainment value (which isn't to say it won't be useful too). The speaker is the Martin Widlake and it's got another one of his arresting titles. I'm chairing this one.

13:30-14:15 - "TimesTen: Anatomy of an In-Memory Database" : Hall 11a

Having attended Susan Cheung's session at OOW2K7 I now know something about TimesTen, and its capabilities. So I know right now it's not appropriate for my current project, but I want to find out more because I think it has some interesting potential for future projects.

14:10-15:10 - "Oracle right to reply on Oracle Licensing" : Hall 1

This is a roundtable facilitated by Mr UKOUG himself, Ronan Miles. I have only just noticed that this is Oracle's response, I guess to the earlier session by from Rocela. I thought it was going to be a chance for us, the customers, to have a therapeutic bitch about Oracle's licensing policies. Apparently not. Given that it is a round table the agenda can be seized by the attendees, so ....

15:20-16:05 - "An Industrial Engineer's Approach to Oracle Management and Performance" : Hall 11b

Like most conferences these days the UKOUG is dominated by features and functionality rather than process. This session from Cisco's Robyn Sands is one of the exceptions. I'm chairing this one.


17:35-18:35 - "11g new features for DBAs" : Hall 1

I didn't get to see Tom Kyte strutting his technical stuff at OOW2K7, because I knew I was going to catch him here.

Monday rounds off with the Bloggers' drinks. Once again the redoubtable Mark Rittman has organised this and arranged for a cash injection from the UKOUG team. Nice one, Mark.

Tuesday, 4th December 2007


09:00-10:00 - "Oracle SQL Developer Latest Features" : Hall 5

I've downloaded the recent SQL Developer patch but haven't really used it much. Sue Harper should provide some inspiration. I'm chairing this one.

10:20-11:05 - "Harvesting the Advantages of a Database Centric Development Approach" : Hall 8a

I haven't heard Toon Koppelaars talk before but I have heard of him. The topic is a key area for me. I'm chairing this one.

11:15-12:15 - "11g new features for DevelopersSs" : Hall 1

A mad dash over to the main hall to see Tom Kyte give expression to the other side of his personality. I'm chairing this one.

13:30-14:15 - "The Duplicity of Duplicate Rows" : Hall 9

For the third year running Dr Hugh Darwen will be giving us a bracing dose of database theory. I'm chairing this one (which is the end of my chairing duties).

14:25-15:25 - "Understanding Statspack" : Hall 1

It's always good to hear Jonathan Lewis talk about anything.

17:30 - 20:00 - "COMMUNITY FOCUS PUBS"

I'll be reprazentin' the Development Engineering SIG at wherever we get allocated. Probably lumped in with the MAD and App Server SIGs. These are birds-of-a-feather things where you can meet people who have the same Oracle interests as you, so do come along.

Wednesday, 5th December 2007


10:40-11:25 - "Every Performance Problem Is One Of Two Things" : Hall 5


James Morle with a promising title. If it was followed by "Discuss" it could fit nicely into a Philosophy exam paper.

12:30-13:15 - "Modelling on the cheap" :

As Mike Yarwood used to, "And this is me." At the time of writing I am still working on the words but I have met all the other deadlines (just!) so I should be alright. However I am open to taking this one off-piste, so if you have some opinions or suggestions about alternatives to expensive CASE tools please bring them along.




I am leaving UKOUG on the Wednesday afternoon. I might attend another session or so, it depends how I feel.

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Tuesday, November 27, 2007

UKOUG 2007: Chair registration - for real

The UKOUG conference website is now open for any delegate to volunteer as a session chair. Yes I know I said this once before but this time it's the truth. I have had the green light from Lauren so it must be okay !

Chairing sessions is not too onerous. We have to remind delegates to switch off mobile phones and fill in the critique forms. We also have to introduce the speakers. However most of them already have prepared their own introductions, so "without further ado" is a handy phrase. The key thing is to ensure the session finishes on time; this means giving the presenter discreet time signals, although most of them should be able to keep their sessions on track without prompting.

The value of volunteering is that you get a free pass to the conference when you chair six or more sessions. I know it is only a few days away, but if your boss is wavering this might just be the extra leverage you need. Sign up now!

Update


At the time of posting the Conference site still displays a message saying you cannot register to chair sessions if you haven't had an invite from Lauren Edwards. Just ignore this and go ahead. I have e-mailed the UKOUG office and I hope the site will be amended soon.

Update again


The website has now be amended.

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Wednesday, November 21, 2007

Simplicity is in the eye of the beholder

Laurent has posted a particularly succinct method for doing bitwise aggregations on his blog. I don't know what practical use it is, but that's another matter. What I liked was his cheeky sign-off, "It is that easy!". Which reminded me of a story from years ago, when I was still in the Ministry of Defence

I was sent on a CORAL 66 course. CORAL was a 3GL intended for real-time programming and it combined keywords in English with some very low level functionality, including the ability to flip individual bits. As a COBOL bunny with a History degree this was this first time I'd ever had to wrangle bitmasks and it made my brain hurt. I wasn't lucky enough to be sent on the subsequent advanced course (five weeks long, those were the days!) but these who did got to build either a missile guidance system or a safety system for a nuclear power station in their exercises. Even on the beginners' course the exercises were fairly hard going.

One involved translating Morse code into letters. I went for a data-intensive solution. I wrote an array with all the letters in the Morse alphabet. This was hard work but the actual processing was quite simple: start in the middle of the array and shift the index left or right depending upon whether the current character is a dot or a dash, halving the offset each time. When there's no further input the index points to the transmitted letter.

There was a very bright chap on the course. We often talk about junior programmers, but this guy was definitely junior, because he was a lance corporal and so everybody else on the course outranked him. Even me: as a civvy I had a notional rank of lieutenant. Most of the trainers were officers but there was a sergeant whose job it was to answer the questions of the non-comm students (they weren't allowed to ask officers questions or indeed initiate any conversation).

Anyway, this corporal's solution consist of a single very dense recursive algorithm which somehow spat out the right answer. However, his code contained just the one comment: "This algorithm is easy to understand so no further explanation is necessary." The trainers didn't understand his algorithm and he knew they wouldn't understand it and they knew that was why he had put the comment in. So they marked him down, for insubordination.

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Monday, November 19, 2007

OOW2K7: Not so San Fran Psycho

Last year OpenWorld seemed crowded, manic and just generally too much. By contrast OpenWorld07 was pretty chilled. There was only one session where I had to wait in a really long queue. There was the one occasion when I was in a long line of people tramping into Moscone South as another long line of people going in the opposite direction to Moscone West. And only once was I in a queue for the restrooms - and that was during OTN Night, when the amount of beer on offer had generated, um, extra throughput. Certainly this morning, as I found myself pressed up against some bloke's wet raincoat in a crammed tube train, I really missed the light and space in San Francisco.

I think this calmness wasn't because there were fewer people - there were more - but because the OOW Team learned lots of lessons from last year. They couldn't really scale out - they are at the limits of what is possible in San Francisco - but they organised things to spread the load as evenly as possible and to avoid the need for too many people moving from building to building. You can figure out your own RAC/PQ metaphor :)

The other reason why this year was calmer was due to the lack of hype. I think many of us were expecting to be continually hit over the head with 11g. But really it was quite low key; lots of sessions on New Features but no real publicity blitz. this is partly to do with the early release of the software taking the edge off things but I also think the licensing issue has something to do with it. Many of the coolest features are chargeable extras to the Enterprise Edition. If you have already got customers who have to rip chips out of their servers to be able to afford to run Oracle it's hard to get a sympathetic audience for news about stuff that's going to cost a whole lot more.

The thing that disappointed me most this year was missing out on presenting in the Unconference. The Unconference sessions were scheduled on the hour. The nature of Unconference is to be different from the conference. But attending one Unconference session meant skipping two regular conference sessions. Wednesday was the only afternoon I had a free two-hour slot but I didn't nab the last remaining 3:00pm slot when I had the chance, so I really have only myself to blame.

The thing I liked best was the series of presentations from the Real World Performance group. I know before the conference I downplayed the significance of the sessions. So sue me. Meeting some old friends from cyberspace and putting faces to new ones was very pleasant too. And at least I didn't suffer too much from jet-lag.

The next OpenWorld is in September 2008. That's only ten months away.... I'm keeping my fingers crossed I get to go again.

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OOW2K7: The Real World Performance Group

The Real World Performance Group is not Peter Gabriel jamming in a muddy field with a bunch of Senegalese drummers. It is a small unit on Oracle's development side, dedicated to understanding database server performance and investigating customers' problems. I included Andrew Holdworth's session on Database performance trends in my schedule having never heard of the group. After that presentation I went to the Group's Round Table session and Andrew's other session the following day, neither of which I had scheduled. He was that good.

The whole series of sessions switched on a number of light bulbs, joining up some of the dots from earlier presentations I had attended. The resulting illumination made me realise I had spent the a large chunk of the last six months barking up the wrong tree. Basically, the sort of session which justifies the whole idea of going to conferences. That's why I've forgone my usual pithy reports in favour of a full-blown dump of my notes from the three sessions. Where the same topic came up more than once I have aggegated all the material in the section which seems most appropriate.

Database performance trends


Andrew Holdsworth opened his session with the observation that most sub-optimal applications are running well enough, because of improvements in CPU speeds and the availability of cheap RAM, which means we can have bigger DB caches. However, in larger databases disk I/O becomes more significant: an SQL statement which requires disk reads for one percent of the data will run one hundred times slower than a query which can be wholly satisfied from memory. Interconnects to remote RAC clusters perform much better than disk I/O.

Most database applications out there are very small. Frequently there are multiple databases on a single server (the most he has seen was forty-nine databases on one host). This is not a problem because the applications are generally used quite lightly, with barely one SQL statement running on the box at any given time. The main challenge is to prevent a single rogue statement stealing all the resources from the other applications. However, there are also a relative handful of really big systems which are rigorously designed and with a single database deployed per host. These applications are owned by significant Oracle customers and have high visibility within the company. Consequently such databases drive the direction of Oracle's development program. These are the sort of databases which demand tuning, because their performance issues cannot be resolved simply by faster CPUs.

The basic practices for good performances are:
  1. Spend time on data modelling. It is easier to tune against good schemas; they are simpler and less error-prone.
  2. Pay attention to cursor and session management, Use the middle tier to protect the database.
  3. Do proper capacity planning. If possible, use intelligent extrapolation from existing systems. Either way, test and validate.
  4. Use database features correctly and appropriately. Always start with the default values and change them only with good reason. (This point was expanded in another session.
  5. Design for predictable perform. Strive for SQL plan stability, but be prepared for dealing with increasing data volumes, which may demand new execution plans.
Andrew devoted a lot of time discussing benchmarks, as the group spend a lot of time running them. Of TPC benchmarks he asked, "Who likes TPC benchmarks? Who believes them?" A vast amount of work goes into them: the time spent optimizing a server for a TPC benchmark is an order of magnitude greater than a customer would spend on tuning their database. Price performance figures are suspect. There is no redundancy (because in the context of a benchmark that inflates the cost without offering any performance advantage), so the configurations are unreliable even dangerous.

They also see a lot of client benchmarks. About nine in ten are dysfunctional: ill-conceived, incomplete and unrealistic. They are time-consuming and expensive to run, and stressful for all concerned: if you inflict a poor benchmark on the RWPG team be sure that they will respond by picking on your cluelessness. Common failings are:
  • an invalid mix of transaction types;
  • no "think time" for the emulated users;
  • poor data sets;
  • in particular, the use of random numbers to seed the data sets so the tests are not repeatable;
  • not allowing for the resources used by the application server;
  • data warehouse tests which fire off 2000 concurrent parallel queries on a twenty CPU box;
  • data warehouse tests which don't distinguish between small, medium or large queries.
His advice is to run it in-house before sharing it with Oracle Support.

His final point was about priorities. The four layers of a database system are, in increasing order of expense: server, interconnects, I/O fabric, storage. Often the cheapest element - the server - is chosen first, and insufficient attention is paid to balancing all the hardware. Storage and network technology has not kept up with CPU speeds: by comparison with them server costs are a rounding error.

The round table


Members of the audience wrote questions on index cards which were passed to the panel. The panel filtered questions according to some strict rules of engagement. The topics had to be of relevance to the largest possible chunk of the audience. On-stage debugging was expressly forbidden. There was some overlap with the preceding and subsequent presentations, so here are a few points which weren't covered in depth elsewhere.

How much SGA is too much? There is no upper bound. Just don't exceed the physical RAM. With DSS we want sorts and joins to write as little as possible to the temporary tablespace so set the PGA to a high value. Aim to have 4-8GB of SGA per core.

The 11g resultset cache uses CPU and RAM. This offers a more favourable price performance than disks, which are just getting bigger without getting better.

The AUTO_SAMPLE_SIZE option with DBMS_STATS is an iterative process. So using it is likely to produce a more accurate sample size than us just picking a percentage value, as we tend not to validate our choice.

There is a problem with bind variable peeking, if the first instances of a query happens to use unrepresentative values. We can solve this through seeding the library cache at start-up by running our key queries with representative bind values.

The answer is always in the data.

Making appropriate use of database technology


The team's original idea for this session had been to cover every database feature. Realising that would have required a four day course (at least) in the end Andrew Holdsworth decided to focus on three key areas:
Parallel Query - lots of people pay for the licences but don't use it properly.
The Optimizer - the part of the database customers find most frustrating.
Session and Connection management - a new but increasing problem.

The code for parallel query has improved considerably over the years but customers are not using it because CPUs have got so fast. The trend is to substitute processor brawn for good design. This is not a sensible strategy with DSS databases, because the chance of resource contention is much greater if the queries take too long to run.

Making Parallel Query work well places a premium on capacity planning. There has to be sufficient bandwidth to support the required throughput down the entire hardware stack. If the server has only got two 100MB HBAs PQ is impossible. Don't just focus on the server; CPUs are the cheap bit ... apart from the licences (AH's joke).

A thumb nail guide to capacity planning. To support a throughput 100MB per second per core (based on the de facto standard unit of a server with four quad-core processors):



4 CPUs x 4 cores x 100MB = 1.6GB of I/O
4 CPUs x 4 cores x 100MB = 1.6GB of interconnect
# of disks = 1.6GB/s / 20MB/s per disk = 80 disks

Note: this doesn't include redundancy for high availability (data warehouses are not allowed to be down anymore).

"Death by indexes". Indexes are great for OLTP but not for DSS which generally rely on aggregation which in turn requires large amounts of data. Indexed reads which accesses only 0.1% of the data performs worse than a full table scan. Lots of indexes will lead to low CPU utilisation. A better approach is to use PQ to haul in large amounts of data quickly and use the powerful CPUs to winnow it: 5ms is a lot of computation time. Partitioning the object to take advantage of query pruning will increase the percentage of relevant rows retrieved, which will further reduce the need for indexes. Use hash partitions for fast joining.

Designing for PQ:
  • Take the database's default for the Degree of Parallelism.
  • Use the resource manage to define the user's DoP.
  • Make the number of hash partitions a power of two.
  • Also, make it a multiple of the DoP.
  • Allow for the concomitant impact on loading, data dictionary management, stats gathering.


The Optimizer is the most maligned, most misunderstood and most misused part of the database. This is in no small part due to Oracle's failure to explain and document it properly. Consequently people tune by Google or witchcraft, which usually means setting underscore parameters. This is a bad idea. Setting init.ora parameters has a global impact: fix one query and break three others. We're setting the values blindly - often underscore parameters have magic values. Most bad execution plans are due to bad stats. The quality of the stats is under our control. We know our data. Whereas the execution of the optimizer is under Oracle's control and it is rocket science. Tweaking the settings of underscore parameters is fiddling with the bit we don't understand instead of fixing the bit we do.

Optimizer basics
  • Run with the default parameter values.
  • Don't make global changes.
  • Hints do not guarantee stability over time.
  • Get the statistics gathering right.
  • Accept change will happen.
  • TEST!
  • When upgrading, accept that your database's previous good performance may just have been luck rather than a testament to your tuning expertise ;)


Gathering stats: start with default values. AUTO everything. Remember, the aim is to get good cardinality estimates.

Table stats are easy. Don't sweat them. An increase in 10% of the rows is unlikely to mean your stats really are stale: think order of magnitude changes.

Columns stats are the key to good performance - size and number of columns, histograms, indexes. Use your knowledge of the data model to figure out whether you have uniform or skewed distributions. Columns with uniform distributions don't need histograms; watch out for bind variable peeking with skewed data. Minimum and maximum values are the ones most susceptible to change (especially for columns populated by sequences) so maybe refreshing the high and low values after each data load is sufficient.

The key to query tuning is to check the correctness of the cardinality estimates. Use DBMS_XPLAN.DISPLAY_CURSOR to see the estimated cardinality alongside the actual cardinality. No need for a 10053 trace (which doesn't give us the real cardinality values anyway).

Connections stress servers, especially SMP, causing latch contention and using lots of CPU. There is a tendency for Java and .Net programmers to be very bad at managing sessions (and cursors). This is because their memory model means they tend to take stuff and not give it back. Connection storms occur when a connection pool floods the server. Connection storms are caused by a problem in the database server which prevents it from satisfying the app server's demands for new connections The app server responds by spawning further sessions. This can escalate quickly to tens of thousands of sessions, which will kill the database server.

Best practice for connection management:
  • 5 - 10 connections per core (I/O dependent);
  • minimise logons and logoffs;
  • avoid parsing;
  • set parameter for minimum and maximum connections per server to the same value.

Final thoughts


I was a bit concerned that I found so much of value in these sessions. Perhaps I had been living in a cave for too long? However, I met up with Doug Burns afterwards and he said that he was going to have rewrite his presentations and whitepapers. As he is Mr Parallel Query I found this quite reassuring.

Andrew Holdsworth observed, when talking about the recommendations for parallel query, we can try this stuff for ourselves but they do it for a living.

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Thursday, November 15, 2007

OOW2K7: Billy Joel - A clarification

An anonymous commenter, as they are entitled to, has objected to my opinions on Billy Joel. I don't think there's any point in debating musical taste. We can't blame somebody for the music they enjoy because it works too low down in the limbic system. They are not a bad person just because they like Billy Joel; I am not a bad person just because I don't.

The thing is, Billy Joel, along with Abba, dominated the airwaves in my formative years. Like the Swedes he is a consummate crafter of earworms. Simply thinking about Billy Joel means I'm going to have the line "Working too hard will give me a heart attack (ack, ack, ack)" running around my brain for ages. I'm just hoping that reciting "running around my brain" will derail Joel in favour of Dillinger. All together now: "A knife a fork a bottle and a cork/That's the way we spell New York".

Right on.

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Push me pull you

One of the examples of bad design Donald Norman discusses in his seminal book The Design of Everday Objects is the door with a handle and a sign saying Push. If the door is meant to be pushed it should have a plate instead of a handle. A plate gives the affordance of pushing whilst a handle gives the affordance of pulling. Hence the need for a Push sign if the door has a handle instead of a plate.

I was reminded of this in the Lori's Diner next to the King George Hotel. Its entrance door swings both ways. Each side of the door has a handle and a Push sign. I still can't quite decide whether that's design genius or design imbecility.

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Wednesday, November 14, 2007

OOW2K7: Simply cowbell

A theme emerges. Oracle announced Oracle VM Server on Monday. Today in his keynote Jonathan Schwartz announced Sun xVM Server. Do two similar products make a trend? It will have to do.

The bulk of Jonathan's keynote was devoted to the proposition that giving away things made good business sense. The argument is, "Developers don't buy things, they join things". Contributing lots of stuff to open source initiatives fosters communities which in turn leads to adoption and that in turn generates demand for the things which Sun sells. Certainly Microsoft has been very successful by treating developers well. I think the difference is that Microsoft still makes a lot of money out of software and operating systems; they really don't care that much about the hardware. Whereas Sun's main revenue stream comes from servers. Java and OpenSolaris and all the other giveaways have been taken up with great enthusiasm; you just need to look at the exhibition hall to understand that developers like free stuff. And of course Java in particularly has spurred the growth of the internet and generated demand for servers and network kit, but that demand is just as likely to be met by Dell or HP as Sun.

Jonathan had a surprize guest: Michael Dell. This was by way of announcing that Dell and Sun would now be partnering. To symbolise the partnership Michael Dell brought Jonathan a Dell T-Shirt. Afterwards, Jonathan confided that backstage Michael told him the T-Shirt was XL, because he was "a CEO now". Jonathan joked, "That's my hat-size not my T-Shirt size."

Larry's keynote was good, a polished performance. He did two short presentations. The first was about Unbreakable Linux and the new VM Server. These are both aimed at promoting Linux. There are now over fifteen hundred enterprises using Oracle's Linux support. The VM server is Linux but it's a new Linux, not the Red Hat code-base which underpins Unbreakable Linux. So perhaps this is the start of the much anticipated Oracle distro. The other presentation was about Fusion Apps. The first Fusion Apps will be released next year. From now on all new Apps will be Fusion - SOA, built-in BI and with SaaS as an option. But it's going to be an evolutionary process. There is no date for the complete Fusion-ization of E-Business Suite.

After that there was a demonstration of the first Fusion App: Sales Force Automation. This is a suite of products - Sales Prospector, Sales Reference and Sales Tools - which will make salespeople more productive. These products leverage social networking principles to facilitate the sharing of information, ideas and documents between sales staff. So the first tools in the new framework are aimed at helping sales people sell more: how very Oracle. The actual tools are fantastically slick. Total eye-candy. The Fusion developers have done a marvellous job with the AJAX widgets. In fact the whole thing looks so lovely I predict a sharp drop in productivity as the sales people spend all day stroking their way through their cache of PowerPoint slides.

Larry then took questions. There were several questions about Fusion Apps and a couple about licencing. Did you know Oracle's preferred licencing approach was to arrange unlimited usage deals with their customers? Me neither, they sure kept that one quiet. Somebody asked, apropos of the Sunday Night Live event, whether Larry had more fun as a start-up or now. The answer was that he much prefers his current situation. Which just isn't fair: he earns gobs of money and enjoys his job more than ever. He only lost his cool once, with a person who attempted to suggest that the profit from Microsoft sales went to the Gates Foundation. Larry cut him off. After acknowledging Bill's generosity he said, "The Gates Foundation is fully funded. If you buy a copy of Microsoft Word the money doesn't go to a person in Peru." Not unless Steve Ballmer has a holiday villa in Lima.

There were two odd things about Larry's session. The first was that Billy Joel came on as the warm-up man. Luckily he hadn't brought his piano - Larry was obviously itching to do his karaoke Uptown Girl. The second oddity was the thing which Larry didn't talk about. The database. Not a peep about the 11g release. So obviously he agrees with me about it being old news. No mention of the rumoured 10.2.0.4 either.

Before Jonathan Schwartz's keynote there was a little piece of Web Two-Point-Noughtery. The screen posed a question and people could SMS their answers. Here are a selection of the answers to the question If I could develop the next killer app it would be:
  • Simple
  • Stable
  • Fast
  • Something to do my laundry
  • Cat cams
  • Portable
  • Mine
  • In the conservatory with a candlestick
  • Simply cowbell
  • Integrate Microsoft and Oracle well
  • Sharks with frikken lasers on their heads
  • Something that takes text messages and projects them on a screen
  • COWBELL!

Update


I have now heard that the 10.2.0.4 patch is coming. Apparently its schedule got bumped to clear the path for the 11g launch. Safe harbour and all that, but it may contain backports of some (minor) 11g functionality as well as bug fixes.

Oh, and if you thought my coverage of Larry's keynote was jaundiced you really ought to read The Register's report. Slammin'!

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OOW2K7: Like, er, Day Two Man

Tuesday at OpenWorld 2007 for me opened with Tom Kyte's keynote. This was something different from Tom. Instead of talking SQL he talked about innovative ideas and the creative thinking process. His key point was that we have to recognise the danger of educated incapacity: too much knowledge can blind us to the existence of certain solutions. The answer is not to know nothing but to use our knowledge wisely. In particular we need to distinguish between what we know that really is true and what we think we know is true but which is in fact assumption or prejudice on our part.

One of the examples of creative thinking he used was an example of tuning from Craig Shallamar. The problem was in a stock control application. The workers would run a report which generated a picklist; the picklist was produced on the printer next to the terminal. They took the picklist and went to the warehouse. The problem was the report took three minutes to run. Craig spent a lot of time tuning the query and shaved about ten percent off the runtime. But ten percent of three minutes still means a long time for the workers to be waiting for the picklist to be printed. Then he noticed that the printer was on a network. So he had it moved to the warehouse. The workers ran the report and crossed over to the warehouse; by the time they had arrived the picklist had been printed. That's fast!

Tom finished up with a lament about the state of developer-DBA relations. Too often DBAs seemed to spend their time trying to prevent developers from doing things whilst the developers spend their days inventing ways to circumvent the DBA. This is a terrible waste of creativity.

Ray Roccaforte opened his presentation on Business Intelligence and Data Warehousing in 11g with a similar philosophical perspective. Indeed, a cosmic question. Given Moore's Law and given the pervasiveness of computers in all aspects of our lives why isn't the quality of our lives doubling every eighteen months? More mundanely, why isn't the productivity of our IT departments doubling every eighteen months?

His answer is that data volumes are growing even faster than Moore's Law. Yahoo had 100TB of data in 2005; two years on it has 250TB. And as disk speeds are lagging behind computing is actually slowing down. Oracle's strategy to deal with this:
  • to scale to any size;
  • put analytics in the database;
  • put ELT in the database.

Incidentally that last point is not a typo: the preferred term is now Extract Load Transform because most of the transformation is done in the database.

Ray showed us a screen filled with 11g New Features for BI and DW - far more than he could cover in the session, so he just ran through some key points. There are further enhancements to partitioning, including the much sought after INTERVAL option and also the REF partition, which equi-partitions parent and child tables on the basis of foreign key values. There is the much reported SQL Resultset caching. There are enhancements to automatic statistics gathering, which will monitor the SQL statements run and gather stats on correlations between frequently queried sets of columns.

The big announcement is probably the changes to the OLAP cube. BI is dominated by aggregation queries. The classical solution is to build Materialized Views, but it is often imposible to build enough MVs, let alone manage and refresh huge numbers of them. In 11g the optimizer will treat an OLAP cube as a Materialized View, and will use query rewrite to access data in the cube, just like with MVs now. This means there is only one object to manage and the refresh window is considerably reduced. The OLAP cube can be interrogated using straight SQL statements, so advanced analytic queries can be added to any application.

Finally Oracle Warehouse Builder is included in the database at no extra cost, although one of the big draws, the Data Quality pack, will be a licenceable option.

Then it was off to the Oracle Magazine lunch. I got invited because I'm on the editorial advisory board. I felt guilty about it because I hadn't been asked to do anything in the last year but Tom Haunert was very magnanimous: it was his fault for not asking the board to do things. I was at the same table as Dr Paul Dorsey, which could have been embarrassing but I guess he doesn't read my blog. Also there was Lonneke Dikmans, the SOA Developer of the Year. Fortunately she and Paul have reached a good-tempered rapprochement on the merits or otherwise of SOA. I had an awkward moment with Tom Clark, CIO of PCA because I was out of practice at convesing with guys in suits. However, he turned out to be a really nice guy, and possibly the most unlikely fellow vegetarian I've met in a long time. I also chattered with Patrick Wolf and Jon Waldron.

Alas I missed the XML presentation but I did get to hear Donald Feinberg, VP and Distinguished Analyst at Gartner on the future challenges of OLTP and Data Warehousing for DBMS tools. This was the first time I had attended a Gartner presentation and it was really interesting. He specifically avoided mentioning any vendors because Gartner has to be neutral and this was an Oracle conference. But much of what he said chimed with other presentations I've attended: management of large data volumes, the importance of data quality, the physics of disk speeds, the importance of analytics. In fact I'm going to have to write up this one separately, once I've had some more time to think about it.

I rounded off the day by chilling out in the OTN Lounge on the third floor of Moscone West. I think the crew have finally found the right formula for the lounge as there's always lots of people there. Steven Feuerstein was doing a Meet The Experts session and I lurked at the back. I even managed to answer a question which Steven couldn't. This only happens one every other year so I claim bragging rights. Somebody asked what was the best way to pivot a table. Steven he wasn't sure but he would probably write some PL/SQL. So I pointed out that 11g had a PIVOT function. He laughed and said he didn't do SQL. Of course not, he's cured his addiction.

Then it was down off to the Thirsty Bear for the Bloggers' Meetup. As well as us old lags there were lots of new faces, which is an indication of just how the Oracle blogging community has grown over the last twelve months. Drink was taken and I think everybody had a good time. Thanks to Mark Rittman and OTN's Vikki Lira for organising it.

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Tuesday, November 13, 2007

OOW2K7: Non-fake tales from San Francisco

One of the things at OpenWorld which continues to astonish me is the rudeness of people in the audience. At the UKOUG we start each session with a reminder to switch off mobile phones, or at least silence them. Here, people not only have their mobile phones on, they actually take calls whilst the presenter is talking. This is not an isolated event: it has already occurred in three out of the seven sessions I've attended so far. Also people conduct conversations during the presentation, and not in whispers either. This is particularly strange given that, outside of the conference hall, Americans are generally far more courteous and better mannered than most English people these days.

Another thing which is shocking to the out-of-town visitor is the sheer number of beggars on the street. One guy I saw yesterday was holding a sign which said I need a girlfriend. I'm not quite sure what he was expecting to be dropped in his cup. There was another guy playing a drumset improvised out of buckets and plastic containers whose sign included his e-mail address. I didn't catch whether it had a PayPal number too.

This year OpenWorld is a green conference. This primarily means that we could choose to have the conference directory as a thick book or a lightweight USB drive. The catch is we need to have a device which takes a USB drive. For those of us who left our laptop at home the dead-tree option is the appropriate technological choice. However I have seen a couple of people attempt to plug their OOW pen drive into a laptop in the Conference internet villages; unsuccessfully, because these babies are totally locked down. The other interesting green initiative is the opportunity to pre-order an Oracle-branded messenger bag which will be made out of recycled conference material. This item will be even more fashionable than that Sainsburys carrier bag because of the absolute coolness of the Oracle logo.

The OTN team are giving away T-Shirts in the OTN lounge. The front features a SQL statement:

SELECT Java, Linux, PHP, DotNet, Python, Ruby
FROM OTN
WHERE Self BETWEEN 'Newbie AND 'Expert'

So, apart from the fact that it doesn't mention PL/SQL and the fact that the statement is invalid due to the missing quote, it's a pretty good attempt.

Gavin Newsom, the mayor of San Francisco would like us all to explore more of the city than a two-block radius of the Moscone Centre:
"You can continue on the F line to Pier 45, walk into the back and experience the fish processing, which is totally frenetic and interesting. Why not see and experience another side, which is the fact that San Francisco remains the largest fish processing center on the West Coast."

Why not indeed.

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OOW2K7: Steven Feuerstein - A clarification

Whilst I'm in the mood for clarification I suppose I should make clear that Steven Feuerstein did not threaten me with a steak knife. He pretended to threaten me with a steak knife and I exaggerated for comic effect.

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OOW2K7: Doug Burns - A clarification

In my post about the ACEs' dinner I described Doug Burns as being extremely jet-lagged. Some people have interpreted this as meaning Doug had taken too much drink. This is not the case. Doug really is jet-lagged. Honest he is. Anytime you see Doug with a beer in his hand you can be sure it's definitely for medicinal purposes only.

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OOW2K7: More about Monday

Bryn Llewellyn's talk overran slightly - there is that much which is new about PL/SQL in 11g - so I only just made it to the Moscone Center for Nitin Vengurlekar's talk on Back-of-the-envelope Database Storage Design. The main thing I took from this talk was that we need to have big envelopes. It was a useful overview for me, as I knew nothing about this area of IT systems. For instance, I learned the difference between throughput and good-put; throughput is the total amount of network traffic whereas good-put is the amount of useful bits transferred i.e. throughput minus network protocol, retransmitted packets, etc. I now know that we can specify our requirements in either MBytes/second or IOPS but they are mutually exclusive. What I don't know is in what scenarios I should be using IOPS rather than MBytes. Transactions/s is a useless metric because it can mean many things to us database practitioners and it means nothing to storage dudes. The other particularly useful part of this presentation was a break down of all the layers of the I/O stack, identifying all of the components which could be a choke-point. A system's I/O is only as fast as its slowest component.

I had a quick wander through the Exhibition hall. I didn't pick up much in the way of loot but AccentureEDS has a really useless but potentially time-consuming geegaw: it's a sticky plasticky bundle of tentacles on a elasticated string - sort of a cross between a yoyo and a primary-coloured Cthulu.

The last session of Monday was Juan Loaiza's talk on Scalability and Performance enhancements in 11g. He opened with some recent benchmarks. He started with the bad boys - 4 million transactions per minute , 1 million physical I/O per second. He said they like these sorts of benchmarks because it's the only time they get to play with such enormous systems; the above mentioned benchmark used 2TB of RAM (which costs about $4m - still a lot of money even at current exchange rates). The interesting benchmarks are the price performance ones: the new ranges of Intel and AMD chips means that Oracle is now outperforming Microsoft in the low-end market as well as the high-end.

The point about the large system benchmarks is that they are the systems of the future. By 2010 Oracle predict there will be at least one 1 PetaByte database out there, at least one 1000 node RAC system and at least one system with 1 TeraByte of RAM. These huge systems are being driven by a number of different trends: government initiatives in healthcare and law enforcement; large internet retailers; and scientific projects in areas like genetic research and particle physics.

The challenge for Oracle is to make such huge resources work as well as smaller resources. For instance, we all know that disks are getting bigger but that their performance is not keeping up. We will soon have 1TB disks, which will be pretty much like tape drives. This is why table compression in 11g is so important. By compressing tables we effectively increase the performance of disks considerably (more data retrieved by each disk read). Furthermore the database can natively interpret the compressed data. Obviously there is a DML overhead but it is a fraction of the gains from improved reads. The problems inherent in backing up a 1PB database are obvious. This is why Oracle has written its own backup utility: the database can use its knowledge of its own state to only backup stuff that needs to be backed up. This can be a lot faster than blindly copying all the system files at the OS level.

It is also obvious why Oracle is still committed to per core licensing. The charges for a 1000 CPU cluster (Enterprise Edition plus RAC plus Partitioning plus all sorts of other 11g goodies) would add up to a hefty chunk of change.

In the Q&A somebody observed that Oracle's own cluster still uses Sun E25K and asked Juan when it is still appropriate to go for SMPs rather than blade clusters. Juan replied that it was a matter of comfort. SMP is a very mature technology but RAC is now mature; leading edge rather than bleeding edge. He did say that he didn't think Oracle would ever purchase another SMP ever again. Larry won't pay for them.

I bumped into Eddie Awad a couple of times yesterday and I kept asking him, "Are you Twittering this?" So at the OTN Night he pulled out his iPhone - Eddie just had to be an earlier adopter - and Twittered Dan Norris. Lo! a few minutes later Dan had located us outside the Jeopardy room. So it can be useful and I will stop being sceptical. OTN night was pretty much the same as last year, only with slightly fewer exotic dancing girls and the introduction of some people from the local D&D guild wandering about on stilts. I'm sure it made sense to somebody. Doug Burns introduced me to Kurt "DUDE" Van Meerbeck and his wife but it was really too noisy to have a proper conversation.

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Monday, November 12, 2007

OOW2K7: First sessions

I'm afraid I skipped the opening keynote of the conference in favour of breakfast with Doug Burns and Dmitri Geilis. It was almost certainly more entertaining and more educational.

My first session of OpenWorld was Dr Paul Dorsey on the "Thick" database. That's thick as in full of business logic rather than stupid. Quite why it's not "rich" database like thin client vs rich client I don't know. Paul said his motivation was to annoy people, which was promising. Unfortunately the sort of people he wanted to annoy - OO programmers, J2EE and .NET middle tier evangelists and open source bigots - weren't in the audience. This is an Oracle conference, so pretty much everybody is going to be signed up at least to the idea of proprietary framework , and most of them will be in favour of putting most if not all the business logic in PL/SQL. Although, as he acidly observed, OTN has drunk the SOA Kool-Aid.

The point being that UI standards change far more often than the database does. So it is acually more important to be UI independent than database independent. He also said that ApEx is not - out of the box - a thick database implementation. It is a product and it is possible to build ApEx applications in a dumb fashion. However, the cost of being dumb in ApEx is less than being dumb in Java.

The second half of the presentation was devoted to an overview of techniques for building thick database APIs. This covered table() functions, Views with Instead-Of Triggers, PL/SQL collections and bulk operations. I'm afraid I found this a bit of a waste of time because surely this is all old hat? But apparently not. At least one person in the audience didn't know about bulk exception handling and so is obviously not using FORALL statements.

Funnily enough, the next session also dealt with building PL/SQL wrappers for SQL, but coming from a different angle. This was Steven Feuerstein, who was seeking to cure our addiction to writing SQL with his "code therapy". His basic arguement is that we should not proliferate SQL statements throughout our programs. Rather we should encapsulate SQL in reusable functions which have proper exception handling and well-structured naming conventions. We should think of SQL in PL/SQL functions as a service which is provided to the actual application code.

We should generate these functions because that's the only way to ensure that proper standards are enforced. Especially in naming conventions, which must be adhered to if the functions are to be reused. I would say that this presentation was an advertisement for the Quest CodeGen utility, except that they're giving it away for free. Steven had one phrase I really liked: deja vu coding. This is when we find ourselves coding the same thing we coded last week. That's a definite sign we have a piece of functionality we really ought to extract to an API for reuse. Of course, the OO crowd, especially the XP lot, have been banging this particular drum for years.

Following on from Steven was Bryn Llewellyn with his session on PL/SQL New Features in 11g. He kicked off with the fine grained dependency tracking: I'm not sure I would have started there, as it's not exactly the most exciting new feature. But I liked his explanation of why Oracle had the validation checking in the first place: it's in lieu of a make file. Real Native Compilation is much more interesting. Until 10g Oracle had "outsourced" the compilation to a C compiler on the OS, because it was easier for Oracle. Unfortunately many sites wouldn't install a C compiler on their production box, so they couldn't take advantage of the performance benefits. I currently work on such a system: the security policy forbids it. Yes this does mean our external C procs are probably sub-optimally compiled but you can't argue with the security policy. So this feature will be very useful to us.

There's also Intra-Unit inlining, which basically counteracts the performance of Feuerstein-approved modularity by duplicating the code from called functions at the compile stage. Result set caching has already been widely talked about. As Bryn says, "You can never have too many caches." His test cases went from ~1000 milliseconds to 0 milliseconds. But apparently not every query will improve by a factor of infinity. The results are guaranteed to be correct in every case but this means that the benefits of caching results may not always be high. Obviously there's a cost to invalidating the cache. What else? DBMS_SQL is here to stay, but only for Method 4 queries. That is when we don't know either the number of defines (selected columns) or the number of binds. For everything else we can now use EXECUTE IMMEDIATE. In case you're wondering, there is no Method 1, 2 or 3.

They are closing the internet village now, so it's time to sign off.

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OOW2K7: What's the story?

The opening salvo in the OpenWorld 2007 campaign was the Sunday Night keynote. When I arrived at Moscone Center at 5:30 the queue for stretched around the block. Literally round the block. I'm sure I wasn't the only person asking whether we were all mad. At least it wasn't raining and at least we all got in. Actually it turned out to be a good thing to be one of the last people into Hall D, because it meant I had to sit through considerably less Billy Joel than the early birds must have had to endure.

Most of the event was devoted to Larry's account of the history of Oracle's thirty years. I'm sure he's told these stories a thousand times already but many of them were new to me. The best story was John Kemp, the first Chief Finance Officer, who used to deliver pizza to the Oracle offices but who was studying Accountancy at Berkley. Also the famous first sale to the CIA was for a product, Oracle version 2.0 (there was no version 1.0) which hadn't been written yet. How times have changed. Unfortunately the speech became less focused and eventually turned into a recitation of people who joined the company over the years.

The rest of the session consisted of some slightly desperate sketches from the cast of Saturday Night Live. There was also a worthy presentation on Oracle's global responsibility programme. There are a number of initiatives in the education arena (mainly encouraging schools and students to use Oracle software). Also, Oracle employees do lots of volunteering. The event was finished off by a pub rock band composed of Oracle employees and customers, fronted by the Senior Vice President for Alliances, playing a song about Oracle rocking for ever. The band was called Eardriver but I'm afraid Hallclearer would have been more appropriate.

Of course I had to leave anyway because of the ACEs' dinner. The Fly Trap is a nice place. I got to drink Pinot Noir from Francis Ford Coppola's vineyard and the food was good. The one problem with these occasions is that the restaurant layout prevents you circulating too much, so you end up talking to a handful of people. Eddie Awad asked my advice about user groups; I'm not sure I completely answered his question but it has stimulated some thoughts which I may blog later. Doug Burns was extremely jet-lagged; you may think that's a euphemism, I couldn't possibly comment. We all got issued with our new Oracle ACE fleeces, which are actually gilets with a large Ace of Spades symbol on the back. I don't know whether the ACE directors' fleeces have the tiara as well. Inevitably Mogens Norgaard wore his for the entire evening. Steven Feuerstein threatened me with a steak knife. These liberal peaceniks are all the same.

So, what is the story?


Is there a big theme? Beats me. One of the Oracle people I spoke to last night said they all don't know what's going on. If there is a big announcement it will be just as much of a surprise to the employees as to the rest of us. One of the ACE Directors who had spent the day in the Directors' briefing sessions said they had been told that there would be no mention of features currently under development. Apparently all that stuff is being saved up for next year's OpenWorld when Oracle are going to make a big deal out of 11gR2.

In the afternoon I was wondering through the Yerba Buena Gardens. A young chap on a bench clocked my OpenWorld pass. Jerking his head at the big tent which is blocking off Howard Street he asked me, "Do you know what the party's about?" "Oracle," I said. "Database software." He turned to his friends and told them, "Computer shit."

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Sunday, November 11, 2007

Joseph Cornell: Celestial Navigator

The Navigating the Imagination, the exhibition of Joseph Cornell's work at the SF Museum of Modern Art is a fantastic experience. Cornell had an omnivorous interest in almost everything - Victoriana, French literature, fairy tales and mythology, the sea, ships, astronomy and the constellations, maps and navigation, nature (especially parrots), ballerinas and film stars, childhood, games of chance, clockwork, mathematics, physics, geometry, architecture - pretty much everything except the internal combustion engine. But he combined this breadth of fancy with a monomaniacal artistic expression: collage and three-dimensional assemblages.

Unlike other artists who experimented with collage as one technique among many Cornell never painted, drew or sculpted. Assembling snippets of pictures, text and objets trouves was all he ever did. This lends the exhibition a repetitive quality which might not be to everybody's taste: if you don't like the works in the first room you might as well skip straight to the exit.

The collages are well-executed: witty, sad, poetical even whimsical. Some of his work bears a resemblance to the collages of other artists (especially Max Ernst, because of his extensive use of Victorian engravings ). The difference is that Cornell was not interested in sensationalising or shocking the viewer. He preferred to create imaginary worlds by drawing connections between apparently unrelated things. There is no political or social commentary in any of the works. They are more like a child's dreams (except for some mildly saucy female nudes in a few of his later pictures).

The boxes are a real revelation. Pictorial representations inevitably flatten them; on the printed page they might just as well be collages too. You have to see them in real life to appreciate Cornell's skill in building up layers and using perspective. Some of the boxes have removable parts or working mechanisms (obviously we're not allowed to actually handle any of them). Some of the works are terribly sad in an undefinable way. One box consists of a grid of shelves, each one holding an identical clear glass bottle containing a small blue marble; it's called An Image For Two Emil(y)ies. Other boxes are genuine amusing. Pantry Ballet (for Jacques Offenbach) features a chorus line of bright red lobsters in gauze tutus.

The texts in the works are surrealistic but coherent. One work, Museum consists of a box of small glass bottles filled with an assortment of things. On the lid of the box is a list of its contents:
Watchmaker's sweepings - Juggling act - Souvenir of Monte Carlo - Chimney sweeper's relic - Thousand & One Nights - Mayan Feathers - White landscape - From the golden temple of Dobayba (conquistador) - Sailors' game - Venetian map - Mouse material

A woman next to me commented to her companion that Cornell must have had a lot of fun building these boxes. I don't think that's the case at all. The finished products are playful, because they often refer to games and toys and his themes are the enthusiasms of a child. But they are beautiful because Cornell had an adult's eye for composition. They are resonant because they are filled with an adult's longing for the certainties and comforts of childhood. And the compulsion to produce these boxes, the obsessive collecting and organising of materials to put in them, that's plain scary and sad.

The exhibition as a whole is melancholic. It's the same feeling we get from looking at ancient ruins. The older works with faded colours and acquired patina are more sympathetic than the more recent stuff. Cornell resisted the relevance of biography in the assessment of an artist's work. Perhaps he feared what his work might say about his own life.

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OOW2K7: It's raining today

Well actually it was raining yesterday, but Scott Walker didn't sing a song called that. In fact it's quite sunny right now but according to last night's weather forecast there are likely to be showers in the north Bay area throughout the week. The news anchors kept saying they needed the rain, like that's supposed to be a consolation. Still, at least this year we get to use the complimentary umbrella included in the conference bag.

I went out for a few beers with John Spencer last night. The bars were all pretty crowded. Turned out the two local college teams were playing that sport the Americans wrongheadedly call football. Guys, it's rugby league in fancy dress. Anyway, the Sam Adams followed by a visit to Lori's Diner kept me awake until the magic hour of 10'O clock. Unfortunately I woke up at 4:30AM this morning. Which is why I'm blogging this in an internet cafe at such a gosh-darned early hour.

I bumped into Wilfred van der Djeil in the lobby of the King George. He was still trying to get his demos working for his presentation tomorrow. I'll keep my fingers crossed.

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Friday, November 09, 2007

My OOW2K7 schedule

The OpenWorld conference starts slowly this year. There is no Oracle Xtreme event to warm up the proceedings . Sunday does feature user group sessions, but I'm not a member of any of the groups so I'm not particularly interested. I think I shall most of Sunday acclimatising, perhaps with a trip to the SF Museum of Modern Art. They've got a major exhibition of Joseph Cornell's work on at the moment. I've only ever seen pictures of his work so I'm ridiculously excited about the prospect of seeing over 200 of his boxes. Also I need to do some shopping: does anybody know a place in SF where I can buy a Beckham LA Galaxy shirt for a six year old boy?

Here is my schedule. It starts strongly. The opening three sessions are from speakers whom I've heard and enjoyed before. The schedule peters out towards the end of the week but then on past experience so do I; it's better not to have too firm a plan.


Sunday, 11 November 2007



5:45 PM - "Keynote: Sunday Night Live" : Moscone North - Hall D

I think I will try to make the opening keynote, as it might be the best chance to share oxygen with Larry. In previous years this event has tended to clash with the ACEs' dinner but this year the OTN team have rescheduled it.

7:30 PM - "ACEs' Dinner" : The Fly Trap Restaurant, 606 Folsom Street @ 2nd

Monday, 12 November 2007


11:00 AM - "'Thick Database' Techniques for Oracle Fusion Developers" : Hilton - Yosemite Room B

Dr Paul Dorsey combines a very deep understanding of database design and development with some strong opinions and a nice line in wit. A promising mixture.

12:30 PM - "Break Your Addiction to SQL!" : Hilton - Grand Ballroom A

Steven Feuerstein (Whom God Preserve) is another great presenter.

1.45 PM - "Oracle Database 11g PL/SQL" : Hilton - Grand Ballroom A

Last year I missed Bryn Llewellyn's talk on enhancements to PL/SQL in 11g. I'm not going to make the same mistake again.

3:15 PM - "Back-of-the-Envelope Database Storage Design" : Moscone South - 310

I don't know nearly enough about storage and the back of an envelope is my avourite design tool so this is an irresistible title.

4:45 PM - "Oracle Database 11g: Next-Generation Performance and Scalability" : Moscone South - 104

My current project (a data warehouse) is still on 9i (I know, I know, it's not my choice). Scalability is an issue, so I want to know if it's worth skipping 10g and going straight to 11. Insert your own Spinal Tap joke here.

7:30 PM - OTN Night : The Westin St. Francis, 335 Powell Street

Loud music, beer, Linux: something for everybody!

Tuesday, 13 November 2007


9:15 AM - Keynote Tom Kyte : Grand Ballroom B - Hilton

"Everyone’s favorite Q&A chief and Oracle expert" will be talking on How Do You Know What You Know.

10:45 AM - "Oracle Database 11g Business Intelligence and Data Warehousing" : Moscone South - 102

Gotta find out more about 11g.

12:000 PM - "Oracle Magazine lunch" : Lulu, 816 Folsom St

I hope to tear myself away in time to make the next session, but it rather depends how good the wine is.

1:45 PM - "Binary XML and XML Index: Scalable, Performant XML Processing for Schemaless XML" : Hilton - Continental Parlor 7 & 8

XML in databases is Teh Suck. On the other hand the pesky X-stuff isn't going away any time soon, so it will be useful to discover any better methods of handling it.

3:15 PM - "The Future Challenges of OLTP and Data Warehouse DBMSs" : Moscone South - 104

A theme is emerging.

4:45 PM - "Best Practices for Oracle Database Auditing" : Moscone West - 3005 - L3

With a bit of luck this presentation will provide a definitive answer for this chestnut of the OTN forums.

7:30 PM - The Oracle Bloggers' meeting : the Thirsty Bear Brewing Co, 661 Howard St

Once more the redoubtable Mark Rittman has organised this meeting. Nice one, Mark.

Wednesday, 14 November 2007


I'm intending to have a go at running an Unconference session today. So I have left lots of space in case a sore head prevents me being first to the whiteboard.

8:30 AM - Keynote, Jonathan Schwartz, Sun Microsystems Inc. : Moscone North - Hall D

I just hope I can get through this without mentioning My Little Pony. Oops.

9:45 AM - "Current Trends in Database Performance" : Moscone South - 102

Um...Bigger, better, faster, by any chance???

12:45 AM - Keynotes, Michael Dell and Larry Ellison. : Moscone North - Hall D

Is it a good strategy to sit through Michael Dell's keynote in order to get a seat in the auditorium for Larry? Or does a wise man just decide to find a TV screen to watch and skip the need to carry an empty bottle?

4:30 PM - "Data Caching Application Deployment Use Cases for Oracle TimesTen In-Memory Database" : Moscone South - 309

People keep suggesting TimesTen as a possible solution to various problems but I really know almost nothing about it. So this is an opportunity to rectify this lamentable situation.

Thursday, 15 November 2007


11:30 AM - "Oracle Database 11g: Can I Do That? Introducing 11g SQL and PL/SQL Enhancements" : Marriott - Salon 9

A last chance to find out more about 11g.

I'm staying in the King George Hotel. I know a few of the other ACEs and sundry bloggers are there too.

And here are my Connect details again. I'm not intending to take a laptop. As I'm not presenting I don't need one and I don't need the hassle of travelling with one. But I shall take advantage of the internet villages to keep in touch.
Join Me at Oracle OpenWorld Connect!

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Wednesday, November 07, 2007

Here comes OOW2K7

Gosh, it's almost time for Open World 2007. Work has been somewhat random and stress-y over the last couple of weeks so I've not really been focused on the upcoming conference. This will be my fourth tour of OOW duty in five years. I have yet to get a handle on this one at all.

Last year the theme of the conference was just sheer size. Oracle had ramped up the scale of the conference to cope with all the acquisitions. The number of attendees went from 29,000 to 41,000. This year's projected attendance of 45,000 is a smaller increase (although it will still be mad).

In 2005 the theme was Fusion. There's recently been some upheaval in the Fusion programme, with slippage in both the scope and the delivery schedule, so it'll be interesting to see what the message will be. They'll have to say something. Let's hope senior executives are hot-pluggable too.

In 2003 the hype was all about 10g: The Grid Has Landed. Even though the actual software was still several months from delivery. Obviously there will be a lot of noise around 11g at this conference. The difference is the database has been available, at least in Linux flavours, for several months now. A large chunk of the audience will be in a position to rebut any wild assertions. So whilst there will undoubtedly be a lot of noise about the new software there will have to be less hyperbole. At least I hope so.

Jason Jones published some useful tips for OOW newbies. I think the key thing is to make the best use of the opportunities for personal contact. A lot of the conference resources will be available as downloads, podcasts, blog articles and whitepapers. So don't get hung up on attending presentations (although make sure you do go to some, just in case your boss asks). Instead, take advantage of the main thing which online can't offer: talking face to face with actual people. I think the evening events tend to be rather too crowded and noisy for networking. So look to some of the extra-mural daytime sessions, particularly the OTN Unconference and the No-Slide Zone which should provide useful arenas to engage with like-minded delegates.

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Friday, November 02, 2007

My PL/SQL Coding Standards

As I mentioned recently a long-running trolling thread in the OTN forum has recently taken a new twist, by reviving the PL/SQL Coding Standards meme. Alas I was wrong in my prediction that the OTN moderators would soon kill the thread. Not only is it still going but the evil genius behind it is still going, and regularly changing their handle. Currently it is my turn to be impersonated.

In order to justify my assertion in that thread I have decided to publish my damn fine standards. So here they are.


APC's Damn Fine PL/SQL Coding Standards



  1. Your code must implement the requirements correctly and completely.
  2. Your code must have a suite of unit and integration tests (preferably automated) to prove it implements the requirements correctly and completely.
  3. Your code must implement the requirements as efficiently and peformantly as possible.



Is that it?


These standards have much to recommend them. They are easy to read. They won't need revision whenever there's a new version of PL/SQL. And they focus on what is really important in code: correct functionality. Of course things such as layout and naming of variables are important, I'm not saying they're not. But a PL/SQL procedure can be neatly laid out, rigourously capitalised and thoroughly commented and yet be full of bugs. In my experience, most coding standards tend to document in tedious detail the things which are easy to standardise - use of upper and lower case, line indentation, etc - rather than the things which actually matter.

Also the strictures of codings standards are rarely revised. I still get handed coding standards which say things like "Always use explicit cursors". So either these standards were written ten years ago or the author has not coded any PL/SQL in the last ten years or the author should be shot. Whichever it is, if the standards document contains such canards, why should anybody pay it the slightest attention?

I intend to expand upon some of these points in future posts. If you want a more regular set of PL/SQL Coding Standards then you should check out the redoubtable William Robertson's site. Alternatively, invest in a copy of Oracle PL/SQL Best Practices by Steven Feuerstein (Whom God Preserve). I don't agree with everything that Steven writes but I firmly believe that if every PL/SQL coder in the world followed these guidelines the overall quality of the global PL/SQL codebase would increase by several orders of magnitude.

Update


The troll has now reverted to an anonymous userNNNNNN handle and restored the original text. Obviously even they have got tired of the joke. Or been stricken by conscience.

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