First off the mark this morning was Mark Lancaster on “Building Advanced APEX 4.0 UIs with Ext JS”, which was an eye-popping demo of some wonderful things you can do when you combine the power of Ext JS with Apex.
Tom Kyte presented via Webinar his “The Best Way – Things You Know” presentation, which I had already enjoyed in Melbourne but it’s always worth revisiting these things – helps to counter the constant wave of opposite sentiment from the other side of the spectrum.
Some years ago I had a quick look at REST, as an alternative to SOAP – but never really got the hang of it. So I was interested in being introduced properly by Chris Muir in his talk “A Change is as Good as a REST – JDeveloper 11g’s REST Web Services”. This double-length presentation was worth attending, he started with an excellent definition of web services, their history and REST’s heritage; explained the power and simplicity of REST, compared and contrasted it with its complex and comprehensive cousin, SOAP; and demonstrated how easy it is to create and expose simple REST web services using JDeveloper.
After lunch, we were entertained by Guy Harrison‘s keynote address, “Technology Trends that have the potential to make big impacts both in our everyday life and as Oracle professionals”. They had to close down all the other conference rooms just to make room for the presentation title in the programme 🙂 But it was a fun talk speculating about the kinds of technology our kids and our kids’ kids will probably be all blasé about.
Connor McDonald fired us all up with “A Better Way of Managing Optimizer Statistics”. He claims that we should stop collecting statistics and stop creating histograms 🙂 – I suspect a number of DBAs are now wondering why they wasted so much of their time (and so much server time) for so long…
I finished the day with Frank Bommarito‘s “Outlines, Profiles, and SQL Plan Baselines” which was a good introduction to the subject and for me was a good overview of some new features I haven’t used.
After a leisurely sleep-in (after a weekend away at the parents’-in-law farm) I made my way to Burswood for the first day of the AUSOUG Perth Conference 2010.
After Roland Slee’s keynote (“consolidate consolidate consolidate!”), I headed upstairs for Steven Feuerstein’s “Golden Rules for Developers” – webinar edition. Unfortunately due to technical issues it started late (no fault of Steven’s) but I think he got the important points across.
Following that was Penny Cookson with “Meet the CBO in Version 11g”. She explained a number of improvements in the Cost-Based Optimizer that came with 11g, including a detailed demonstration of adaptive cursor sharing.
After lunch I decided to take in a DBA session – Guy Harrison spoke about how Oracle runs on VMware, which had some very interesting info about the difference between Full Virtualisation, Paravirtualisation, and Hardware-Assisted Virtualisation. A lot of it went over my head but I got a slightly better picture of what’s going on when I run an OS in a VM, as well as how proper memory and CPU allocation can make a huge difference to the performance of Oracle in a virtual environment.
I lost count of how many great tips Scott Wesley gave in his “‘n’ Methods to Improve APEX Performance” presentation – but there were a lot of great ideas, many that are simple and easy to implement, which can make a big difference to the performance of your Apex applications.
It was great to see the level of interest in APEX Themes and Templates – if you’d like to look through the bits that I skipped over, feel free to download my presentation from here.
Another good day in Melbourne. Heard Richard Foote talk about Indexing New Features in Oracle 11g release 1 and 2. One thing he demonstrated was the creation of an index on only part of a table – normally I’d use a function-based index for this sort of thing, but his technique results in an index that is useful without adding strange predicates to all relevant queries in the application; it involves creating a globally partitioned index, in an UNUSABLE state, then rebuilding only selected partitions. This could be very useful for customers who have the partitioning option.
Of interest to me was Discovering the Power to Save the Planet, presented by Robin Eckermann (Smart Grid Australia) – having worked for a short time at Western Power, it was interesting to hear his perspective on the future of the generation and distribution of power. He compared the state of the art in power to broadband, as it was 15 years ago – and asserts that the smart grid will enable all sorts of new applications for customers to regulate their demand intelligently, and is essential for the coming wave of electric cars.
After that was Steven Feuerstein’s second talk, “Golden Rules for Developers“, which was well worth a good listen. I recommend you download and read the powerpoint if you missed it. If you take even just one of his recommendations (e.g. Don’t Repeat Anything, Don’t Take Shortcuts, Build On A Foundation, Don’t Code Alone), I think you will improve the quality of your code, reduce the cost of maintenance for your employer/client, and be much more satisfied with your work. I certainly intend to – I’ve been guilty of “starting from scratch” many times – I do carry around a portable hard drive with a large collection of bits and pieces I’ve collected along the way, but nothing I can just plug in and use with confidence. Steven also gave another PL/SQL talk at the end of the day, this time for DBAs, and that was interesting to me (as a developer). If you’re a DBA, but think that you have no need for PL/SQL, think again.
After that, during lunch, Steven announced the winners of the previous day’s quiz – and wouldn’t you know it, I won 🙂
After a scrumptious breakfast at the Armoury I headed in what I believed was the general direction of the Melbourne Convention Centre – after making a wrong turn I eventually spotted a footbridge over the river that rung a bell from my GoogleEarthing; after taking some photos I was finally at InSync10.
The first session was Connor McDonald’s 11g Features for Developers, which was an eclectic mix of bits and pieces you won’t get from reading the New Features Guide or from Oracle Marketing, along with some gratuitous use of photos of his kids.
Steven Feuerstein didn’t present next, instead he made us think by running a Developer Quiz. Much like the PL/SQL Challenge (at which, by the way, you should sign up this instant if you haven’t already), it was fun and challenging, and I suspect everyone learned at least one new thing. Me, I learned what SUBSTR returns if the 2nd parameter (which normally starts at 1) is zero. As always, Steven was completely open to criticism, and with Connor and Tom in the room he certainly didn’t get off scot free 🙂
As it happened, I happened to disagree on one question, which was regarding the USING clause and how many bind variables must be supplied to a given statement. One of the responses (from memory) was that “you must always supply as many bind variables as there are placeholders”. I knew that if the statement being executed was SQL, the number of bind variables must match the number of placeholders, even if some of them have the same names (e.g.
INSERT INTO emp VALUES (:a, :b, :a, :b) would require four bind variables). However, I also knew that if the statement is a PL/SQL block, each unique placeholder requires a different bind variable – if the placeholder appears more than once in the block, you don’t repeat the bind variable in the USING clause. I therefore ticked this answer as “correct” – if, for example, the block was
BEGIN call_something(:a, :b, :a, :b); END;, you would have to provide two bind variables, because that is how many distinct placeholders there are in the block.
There was some discussion about this, because the answer was marked incorrect – according to Steven the number of placeholders in the block above is four, not two – and I agree that the meaning of a “placeholder” is different to a “bind variable”, although I usually speak as if to conflate the two ideas. However, I still hold to the opinion that a “placeholder” in the context of a PL/SQL block is a reference to this:
:a, and I would say that the one placeholder
:a appears twice in the PL/SQL block. I believe I have the documentation to back me up:
If the dynamic statement represents a PL/SQL block, the rules for duplicate placeholders are different. Each unique placeholder maps to a single item in the
USING clause. If the same placeholder appears two or more times, all references to that name correspond to one bind argument in the
USING clause. In Example 7-7, all references to the placeholder
x are associated with the first bind argument a, and the second unique placeholder
y is associated with the second bind argument b.
(emphasis added) Source: Using Duplicate Placeholders with Dynamic SQL
This is really just an argument over semantics, so no big deal. Some of the other questions had much more interesting discussion, so it was well worth attending. If you’re in Perth on Friday, Steven is running it again (I won’t be able to attend, unfortunately). I presume he will be using different questions…
After that I went for a walk through Melbourne, since it was sunny outside. The climate in Melbourne, I discovered, is a tad different to Perth. Wandering along the riverside, I ended up experiencing a blast of all four seasons within the space of an hour – a lovely spring breeze, a somewhat warmish summer, then a cold blustering windy autumn (a bit out of order that) – there was a few seconds where it was difficult to remain upright – followed by a sudden rainstorm. I managed to find shelter under one of the many bridges that cross the river, waited for about ten minutes, then was able to walk back to the centre without getting any wetter. In fact, by the time I got back to the convention centre it was sunny again.
After a light lunch it was my turn to talk, and I think my presentation on APEX Themes and Templates went quite well. I appreciated the comments and questions that came back, and had some further discussion with a few people afterward as well, which was good.
I forwent Connor’s excellent Partitioning presentation which I’ve heard before, instead heard Kyle Hayle – Database Performance Made Easy – demonstrate the virtues of database tuning using a tool such as the one he’s produced at Embarcadero. I haven’t made use of many graphical tuning tools before, preferring just “the numbers”, but Kyle made an excellent case for the use of pictures instead of words for not only visualising the workload on the database (such as presented by Oracle’s Enterprise Manager, which Kyle had a hand in), but also for visualising the structure of a query. Personally, I’ve grown accustomed to using the traditional explain plan and I suspect I’ll probably continue to, but the Embarcadero product does have some features that automate some of the work I’d normally do by hand (such as examining the constraints on the tables and obtaining filter percentages).
Last of all, Tom Kyte presented The Best Way, in which he laid to rest for once and for all the answer to the age-old (and oft-repeated) question, “what is The Best Way to …?”. Finally, we can stop arguing over which way is worthy of being called Best Practice, and get on with the job 😉
Went out for a nice dinner at a small japanese restaurant, which had a great cozy atmosphere, and on the way back to the hotel was surprised by these great explosions of flame from these pillars. I could feel the heat from hundreds of meters away. At the end, a quick stop at a store allowed me to procure what I’d been coveting all day: Farmer’s Union Iced Coffee.
It was great to catch up with former colleagues at the conference today. As I go from site to site I’m gradually collecting more and more former colleagues and it’s great to hear how they’re going and what they’re working on.
Howard Ong gave a good review of Oracle’s new Data Modeller. Sounds like it’s got a lot of promise – but it’s very new and misses some features (e.g. support for functions, procedures with parameters, packages, and DDL change script generation) that I’d expect in an Oracle CASE tool.
I was happy to see a good level of interest in Python at my talk after lunch. If you’re here because you want to have a peek at all the slides I skipped, you can view or download it from here [Python_and_Oracle_Fast.pdf].
Unfortunately I had to leave soon after that to pick up my car from the autoelectrician, tomorrow I should be able to stay all day.