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I just presented my last session this year on Trivadis DevDays 2020. Like most conferences in 2020, it was a virtual event. 13 of 16 conference sessions in the last twelve months I was presenting from home. Time to look back to this very special year.

When I travelled to Milan and Rome for the ITOUG Tech Days 2020 end of January, I never thought that this might be my only real conference this year. I expected a similar year than 2018 and 2019, when I had the opportunities to speak at many Oracle conferences in Europe and USA. For this year, I already had commitments for APEX connect in Germany, RoOUG ConTech in Romania and BGOUG Spring Conference in Bulgaria. Beginning of March, two of my submitted presentations for Kscope20 in Boston were accepted. So, It seemed to be a fully booked conference year again. But I was wrong with my assumption…

Many international speakers attended the ITOUG Tech Days, and because we had a day off between the first event in Milan and the second one in Rome, we had a great chance for sightseeing in Rome. Warm weather, blue sky, good food and drinks! We even had an ACE lunch and a speakers dinner on the same day. Socializing is an important part of every conference, and here in Rome were had the perfect circumstances for this.

Rome Sightseeing
Sightseeing with ITOUG speakers in Rome. Source: Twitter

During our stay in Rome, two chinese tourists in a hotel not far away from our hotel were tested positive for the coronavirus. I was glad not to stay in this hotel, so this emergency situation, the first two COVID-19 cases in Italy, will not affect us. Again, I was wrong with my assumption…

Few weeks later, the situation changed dramatically. The coronavirus travelled through Italy, Switzerland, all European countries and the whole world. And none of us travelled anymore. On 16th of March, the Swiss government declared a national lockdown, most of the borders in Europe were closed. So, no conferences anymore this year? Fortunately, I was wrong with my assumption…

Many Virtual Conferences

Three days after the beginning of the lockdown in Switzerland, I had my first virtual presentation. In AskTOM Office Hours, I was able to present my “SQL Horror Show” session. I presented these slides on several conferences in 2019, but this was the first time in a webinar session. For me, it was a new experience to give a presentation from home. The AskTOM session had nothing to do with the current corona situation. Chris Saxon asked me in Rome if I would like to give this presentation as a virtual session.

AskTOM Office Hours
AskTOM Office Hours, speaker’s view. Source. Twitter

This was not the last time that I had the opportunity to present from home. It was impressive to see how fast many existing and new conferences were switched to virtual. Just two weeks after the lockdown situation started in most European countries, a new virtual event ACEs@home was introduced. Thanks to Gianni Ceresa, Christian Berg and Francesco Tisiot for the quick organisation and to invite me to speak in “episode 1”.

Since April, I was able to speak at 13 virtual conferences, webinars and meetups: ACEs@home, APEX connect online, AIOUG Oracle Groundbreakers Yatra 2020, ODTUG Analytics Webinar, TDWI Roundtable Basel, Oracle Groundbreakers EMEA Virtual Tour, Trivadis Performance Days, SOUG Virtual Days, DOAG Conference 2020, Data Modeling Meetup Munich, UKOUG Conference 2020, IT-Tage 2020 and – just now – Trivadis DevDays 2020.

Although these were a lot of different events all over the world, the feeling of presenting online is always the same: Looking into a camera, sitting alone in my office at home, I have no clue about the audience listening to my presentation. It makes no difference whether I present for attendees in Switzerland or in India, whether 10 or 100 people are listening. In most of the virtual sessions, the only possibility to ask questions is in a chat or a Q&A window. It is quite common that only few people (or none at all) ask questions. This was unusual and disappointing for me. Most speakers will agree with me and have had similar experiences.

On the other hand, it was a chance to attend conferences that I would not have joined onsite. For example, I wouldn’t have submitted a session for a conference in India, nor would I have been able to speak on two conferences in Germany and United Kingdom on the same day. This is only possible for virtual conferences.

My Presentations this Year

Some of my sessions this year are existing presentations that I showed on previous conferences (with a real existing audience) before. Here an overview of the my existing presentations that I reused (sometimes in an updated version) in 2020:

  • Incremental Statistics: From a Nightmare to a Fast Solution: This session about improvements of synopses calculation for incremental statistics in Oracle 12.2 I gave on several conferences in 2018 and 2019. This year, I was presenting it at the ITOUG Tech Days in Rome.
  • Avoid “Horror Queries”: Keep Your SQL Simple and Fast: The “SQL Horror Show” is my personal “bestseller” so far. After the presentations at ITOUG Tech Days in Milan and Rome, in AskTOM Office Hours and AIOUG Yatra conference, I presented it 13 times since 2017. The version of AskTOM Office Hours is also available on video.
  • Query Rewrite: The Supreme League of Materialized Views: The only time so far I was able to present this session in front of an audience was at the DOAG conference last year. This year, I showed it virtually at ACEs@home (see video), Trivadis Performance Days and the UKOUG conference. For the Performance Days I created an “extended version”, because the sessions there are 80 instead of 45 minutes.
  • The Night is Too Short: 10 Tips to Improve ETL Performance: The presentation is based on a blog post and contains 10 general tips how the performance of ETL jobs in a data warehouse can be improved. In 2020, I showed it twice (in German) at the SOUG Days of the Swiss Oracle User Group and at IT-Tage. While the IT Days 2020 were planned as a virtual conference from the beginning, I was hoping to join the SOUG Day physically in Basel. But this event also had to be switched to virtual at short notice. If you know German, you can watch the SOUG Day session on video.
Some of my days (and nights) in my office at home, I spent in developing three brand new presentations, and extended an existing one with several improvements. I hope to get a chance to show these sessions somewhen in the future on real conferences for a real audience, not only in front of a camera. This year, at least some virtual presentations of the new sessions were possible:
  • Craft Beer in the Cloud: A Data Warehouse Case Study: This case study, based on an example Data Vault model for our microbrewery Monsterbräu, was originally developed by Andrea Kennel and me for DOAG 2019 in Nuremberg. We were pleased when the session was also accepted for Kscope20 in Boston. Unfortunately, the conference was cancelled. Instead of traveling to Boston, we presented the session three times this year on virtual events. We explain how to load dimensional Data Marts from a Data Vault schema. For the live demos, we use an Oracle Autonomous Data Warehouse. In an ODTUG Analytics Webinar, the focus was mainly on the Oracle Cloud implementation, while we talked more about Data Vault in general on the TDWI Roundtable and Data Modeling Meetup sessions. On all three events, not only the presentation was virtual, but also my implementation of the data marts. While Andrea showed how to load the dimension and fact tables with efficient SQL statements, I implemented the same logic with views as a “Virtual Data Mart”. In our first presentation at DOAG last year, we used an “Always Free” account in the Oracle Cloud. When we compared the query performance, my solution had no chance compared to Andrea’s implementation. Fortunately, I have better conditions this year: As an Oracle ACE Director, I can use a real Oracle Cloud account for the demos. Unlike the “Always Free” account, the number of CPUs is not limited to 1. So, before every presentation, I scale up my ADW database to 8 CPUs to have a chance in the performance comparison with Andrea.
  • “Make it faster”: Myths about SQL Performance: In this presentation, which I presented on APEX connect online (see video) and Oracle Groundbreakers EMEA Virtual Tour, I explain why several common myths about SQL performance tuning are not true. The presentation contains two detailed live demos about the usage of indexes and hints. All the examples and demo scripts of this session are inspired by James Bond movies. The reason has to do with the coronavirus situation: During the lockdown in March and April, we had a lot of time at home in the evenings and took the opportunity to watch all James Bond movies once again.
  • Homeoffice: Temporäre Notlösung oder Chance für die Zukunft?: If a German speaking person tells you: “I am doing home office”, don’t be surprised. “Homeoffice” is the German term for working from home. In my first non-technical session I ever showed on a DOAG conference, I was speaking about my personal experience after 8 month of working from home. I compared the advantages and disadvantages of different ways of working and asked myself for which activities we will continue to work from home in the future – after the coronavirus crisis. I’m sure we will not go back to the “old days”, because there are many pros when you can work from home. But not for all activities: For example, a virtual conference is never the same as a real conference where you can meet people in the sessions, during coffee breaks and social events.
  • Interessante SQL-Erweiterungen in Oracle 20c: The second session I prepared for DOAG 2020 was about new SQL features in Oracle 20c. I spent a lot of time to prepare this presentation and some demo scripts. Before I speak about a new feature in a presentation, I really want to understand it. So, most of the preparation time I used to test and understand the new features. After that, creating the slides was the least of the work. As I wrote in my last blog post, preparing a live demo can be quite hard, especially if the demo does not work at the end. Today, I presented the session again at the Trivadis DevDays 2020, but with several changes. Oracle 20c was only a preview release and was replaced by version 21c at the beginning of December. Because I do not want to show an outdated presentation, I had to install a new 21c database in the Oracle Cloud, update several slides, replace links to the documentation, and change the title to “Interessante SQL-Erweiterungen in Oracle 21c”.

event frog
My only live spectator during my presentations this year. Thanks to for this gift.


When I started to write this blog post, I planned to use the title “2020: A Year to Forget”. But this would be unfair. Of course, 2020 was not a successful year for most of us, but compared to many other people, I’m healthy and still in a comfortable situation. I had enough work (this is one of the reasons why I only published very few blog posts this year) and was able to speak on many virtual conferences, as described above.

We also had a successful year in our family: I was promoted to an Oracle ACE Director, my wife Andrea Kennel became an Oracle ACE Associate, and our son Patrick Schnider finished his PhD in Computer Science at ETH Zurich and started a new job as postdoc at the University of Copenhagen. For this, he moved to Denmark – physically, not only virtually.