Results from the Q3 2013 PL/SQL Championship now available!

You will find below the rankings for the 2013-3 championship; the number next to the player's name is the number of times that player has participated in a championship.

Congratulations first and foremost to our top-ranked players:

1st Place: Michal Cvan of Slovakia

2nd Place: mentzel.iudith of Israel

3rd Place: Janis Baiza of Latvia

We do not see 100% correct on the championship very often. Michal took his time, answered with care...and walked away with the top prize! Iudith was not far off Michal's flawless accuracy, with just one incorrect choice. Janis took a somewhat different approach, cruising through the quizzes in just 14-1/2 minutes and still scoring quite a high level of correctness.

Congratulations to everyone who played in the championship. I hope you found it entertaining, challenging and educational. And for those who were not able to participate in the championship, you can take the quizzes next week through the Practice feature.

Steven Feuerstein

Note: Below the table of results for this championship, you will find another list showing the championship history of each of these players.

Rank	Name	Country	Total Time	% Correct	Total Score
1	Michal Cvan (10)	Slovakia	31 mins 08 secs	100%	3127
2	mentzel.iudith (12)	Israel	26 mins 41 secs	96%	3066
3	Janis Baiza (8)	Latvia	14 mins 28 secs	88%	3011
4	Jeroen Rutte (6)	Netherlands	21 mins 05 secs	88%	2878
5	Peter Schmidt (5)	Germany	21 mins 56 secs	88%	2861
6	Ivan Blanarik (7)	Slovakia	24 mins 50 secs	88%	2803
7	Ingimundur Gudmundsson (2)	Norway	31 mins 38 secs	88%	2667
8	_tiki_4_ (5)	Germany	20 mins 13 secs	80%	2596
9	Frank Schmitt (7)	Germany	20 mins 43 secs	80%	2586
10	Andrey Zaytsev (1)	Russia	29 mins 03 secs	84%	2569
11	Viacheslav Stepanov (11)	Russia	30 mins 55 secs	84%	2532
12	Frank Puechl (3)	Germany	17 mins 37 secs	76%	2498
13	Niels Hecker (13)	Germany	10 mins 47 secs	72%	2484
14	Pavel Vorontsov (1)	Russia	16 mins 23 secs	72%	2372
15	james su (7)	Canada	20 mins 07 secs	72%	2298
16	Tony Winn (4)	Australia	23 mins 33 secs	72%	2229
17	Siim Kask (12)	Estonia	24 mins 36 secs	72%	2208
18	Stelios Vlasopoulos (9)	Belgium	30 mins 48 secs	72%	2084
19	Denis Ivin (1)	Russia	31 mins 44 secs	72%	2065
20	Tobias Stark (3)	Germany	32 mins 21 secs	72%	2053
21	Zoltan Fulop (6)	Hungary	31 mins 49 secs	68%	1914
22	Giedrius Deveikis (4)	Lithuania	11 mins 31 secs	56%	1870
23	Hamid Talebian (1)	Netherlands	34 mins 19 secs	68%	1864
24	Thierry Poels (6)	Belgium	25 mins 55 secs	60%	1732
25	swart260 (6)	Netherlands	18 mins 49 secs	52%	1574
26	Rakesh Dadhich (4)	India	16 mins 00 secs	48%	1480
27	Oleksiy Varchyn (1)	Norway	30 mins 19 secs	40%	894
28	Rich Barnhart (1)	United States	25 mins 12 secs	36%	846

Championship Performance History

After each name, the quarter in which he or she played, and the ranking in that championship.

Name	History
Michal Cvan	Q3 2010:22nd, Q4 2010:25th, Q3 2011:21st, Q1 2012:11th, Q3 2012:14th, Q4 2012:14th, Q1 2013:14th, Q2 2013:11th, Q3 2013:1st
mentzel.iudith	Q4 2010:4th, Q1 2011:17th, Q2 2011:23rd, Q3 2011:5th, Q4 2011:4th, Q1 2012:7th, Q2 2012:16th, Q3 2012:33rd, Q4 2012:4th, Q1 2013:2nd, Q2 2013:7th, Q3 2013:2nd
Janis Baiza	Q2 2010:3rd, Q4 2010:7th, Q3 2011:9th, Q4 2011:1st, Q3 2012:23rd, Q1 2013:4th, Q2 2013:4th, Q3 2013:3rd
Jeroen Rutte	Q3 2010:19th, Q3 2012:10th, Q4 2012:11th, Q1 2013:8th, Q2 2013:18th, Q3 2013:4th
Peter Schmidt	Q3 2010:2nd, Q4 2010:14th, Q3 2012:27th, Q2 2013:5th, Q3 2013:5th
Ivan Blanarik	Q1 2012:3rd, Q2 2012:12th, Q3 2012:16th, Q4 2012:24th, Q2 2013:6th, Q3 2013:6th
Ingimundur Gudmundsson	Q1 2013:25th, Q3 2013:7th
_tiki_4_	Q4 2011:26th, Q1 2012:16th, Q2 2012:20th, Q4 2012:8th, Q3 2013:8th
Frank Schmitt	Q4 2011:22nd, Q2 2012:2nd, Q3 2012:21st, Q4 2012:3rd, Q1 2013:13th, Q2 2013:1st, Q3 2013:9th
Andrey Zaytsev	Q3 2013:10th
Viacheslav Stepanov	Q1 2011:8th, Q2 2011:4th, Q3 2011:13th, Q4 2011:19th, Q1 2012:17th, Q2 2012:9th, Q3 2012:6th, Q4 2012:21st, Q1 2013:18th, Q2 2013:22nd, Q3 2013:11th
Frank Puechl	Q3 2012:26th, Q1 2013:15th, Q3 2013:12th
Niels Hecker	Q2 2010:2nd, Q3 2010:1st, Q4 2010:15th, Q1 2011:6th, Q3 2011:7th, Q4 2011:10th, Q1 2012:2nd, Q2 2012:3rd, Q3 2012:2nd, Q4 2012:7th, Q1 2013:6th, Q2 2013:3rd, Q3 2013:13th
Pavel Vorontsov	Q3 2013:14th
james su	Q3 2010:56th, Q2 2011:7th, Q3 2011:11th, Q4 2011:14th, Q2 2012:15th, Q1 2013:7th, Q3 2013:15th
Tony Winn	Q3 2010:16th, Q2 2013:17th, Q3 2013:16th
Siim Kask	Q1 2011:28th, Q2 2011:6th, Q3 2011:10th, Q4 2011:3rd, Q1 2012:8th, Q2 2012:4th, Q3 2012:31st, Q4 2012:10th, Q1 2013:11th, Q2 2013:16th, Q3 2013:17th
Stelios Vlasopoulos	Q4 2010:37th, Q4 2011:20th, Q1 2012:27th, Q2 2012:30th, Q3 2012:1st, Q4 2012:1st, Q1 2013:27th, Q2 2013:23rd, Q3 2013:18th
Denis Ivin	Q3 2013:19th
Tobias Stark	Q1 2012:32nd, Q3 2012:3rd, Q3 2013:20th
Zoltan Fulop	Q1 2012:15th, Q2 2012:26th, Q3 2012:22nd, Q4 2012:17th, Q1 2013:22nd, Q3 2013:21st
Giedrius Deveikis	Q2 2012:5th, Q3 2012:9th, Q3 2013:22nd
Hamid Talebian	Q3 2013:23rd
Thierry Poels	Q3 2011:22nd, Q1 2012:24th, Q1 2013:26th, Q3 2013:24th
swart260	Q2 2012:21st, Q3 2012:25th, Q4 2012:25th, Q1 2013:29th, Q2 2013:26th, Q3 2013:25th
Rakesh Dadhich	Q2 2012:10th, Q1 2013:23rd, Q2 2013:28th, Q3 2013:26th
Oleksiy Varchyn	Q3 2013:27th
Rich Barnhart	Q3 2013:28th

Questions Arising from First Database Design Quiz

[This post is from Chris Saxon, manager of the weekly Database Design quiz.]
 
The database design quiz for the 12th-18th October covered implementation of  a preferred address feature for customers. The first choice in the answers added a DEFAULT_ADDRESS_ID column to the customers table. 

This answer was marked as correct, however many players selected this choice as incorrect and a few objected on the basis that no foreign key was defined (on the DEFAULT_ADDRESS_ID column). 

The requirements in the question stated that customers could select "at most one" of the addresses to be their preferred address. By definition the PLCH_CUSTOMERS.DEFAULT_ADDRESS_ID meets this, as it's only possible to store one default address per customer. In my opinion, adding a FK to this column to an address table while a very desirable action isn't strictly necessary to meet the "at most one" requirement. 

This also brings up a wider concern I have with these quizzes regarding foreign keys. This week's quiz (18^th-25th October 2013) includes a CURRENCY_CD field. If I was designing "for real", there would definitely be a FK on this column to a CURRENCIES table. I excluded the FK and additional table from the question however to keep it shorter and easier to read. There are a couple of other "missing" FKs and tables from the question, which also aren't strictly necessary to answer the question. 

Based on the response to the default address in the previous quiz, some players may feel these are necessary for some of the choices to be correct. 

So I would like to gather your thoughts on how we should handle these issues. 

The questions I have are: 

• If a quiz includes a choice with fields that reference a key from another table, is it necessary to define a FK for the choice to be correct? (If the question states that we must do something, for example to use valid addresses, I certainly agree that a FK would be necessary) 
• In general, should questions include as many FKs and tables as possible? Or should FKs only be listed where directly impact the correctness of some of the choices? 

Please let us know your thoughts on this!

Also, remember that we will not publish any comments that reference the details of this week's quiz! No spoiler alerts!

Feedback Needed: A new vision for the PL/SQL Challenge

We started the PL/SQL Challenge in April 2010 with a daily PL/SQL quiz. Over the years since, we have added weekly APEX, SQL and Logic quizzes, as well as monthly quizzes, quarterly championships and much, much more: over 1,200 to date!

Through it all we published five new quizzes on PL/SQL each week, come rain or shine, holiday or workday. And it should come as no big surprise, given that this whole site was my idea (Steven Feuerstein), that I have written more quizzes than everyone else combined: over 1,000. Wow.

I've gotten pretty good at it (productive, that is) and I actually do enjoy it. 


Yet I now feel that the time has come to end the daily quizzes. I know that many of you may have strong feelings about this, so I would like to share (a) my reasons for feeling this way and (b) what I would like to do in place of the daily quiz.

I plan to put these changes into effect on 1 January 2014, so I very much want your feedback.

Here are my reasons:

1. It's very time consuming to write five quizzes per week, along with verification code and resources. It's also quite a job to review all these quizzes, and much of that effort has fallen at this point to a single, valiant player: Elic.

I have greatly enjoyed writing these quizzes. I've learned even more about PL/SQL in the process and, certainly, feel good about the impact of these quizzes on thousands of developers around the world.

But the bottom line is that by committing so much of my time to these quizzes, I have that much less time for other activities, both related to Oracle technologies and completely distinct from them.

And I must tell you that whether it is a mid-life crisis (I just celebrated my 55th birthday) or just one more human being coming to his or her senses, I feel more and more strongly with each passing day that I need to spend more time out in the natural world, away from computers and the Internet and plastic.

2. It's quite a burden on our reviewers to ensure a high quality for five quizzes each week. For a while, I had four-five PL/SQL developers checking my quizzes (well, usually 2-3 for any given quiz), but lately the main responsibility has fallen on our most excellent and diligent reviewer, Elic. He shows no signs of wear and tear, but it worries me....

3. Hmmm. I guess that's really about it. :-)

So what would I like to do instead? (with the PL/SQL Challenge, that is. Check out feuerthoughts.blogspot.com for occasional disclosures about what I plan to do with the rest of my life, overall. My views on that have been changing a lot in the past year.)

Here's what I am thinking about right now:

Offer THREE weekly quizzes on PL/SQL, as follows:

1. The PL/SQL Challenge: a weekly quiz authored by me that covers the gamut of PL/SQL features, as we have been going with the daily quiz - just once per week. See? I am not going to stop writing quizzes entirely!

2. The Community PL/SQL quiz: a weekly quiz that is authored by others (anyone but Steven Feuerstein). Currently we restrict how many questions authored by players can be used per quarter to just three. At least one player (Iudith Mentzel) has written lots of great questions that could be played and appreciated better with this new weekly quiz. And I hope that having a weekly quiz specifically showcasing the knowledge and creativity of others will encourage you to submit your own!


3. Deja Vu PL/SQL: a weekly quiz that features a question previously played in the daily PL/SQL quiz. Of course, if you spend lots of time practicing past quizzes, these will, over time, get ridiculously easy for you, but hey there's nothing wrong with that. You are internalizing programming patterns, leading to improved productivity and code quality in your own work. I am certain of it!

The PL/SQL Challenge quiz will be the primary quiz for rankings and qualifications for championships (more on that below). We would also rank the Community PL/SQL and Deja Vu PL/SQL quizzes, but they would not be used directly to qualify for championships. Instead, some players of these quizzes would qualify through a variety of special rules (play all quizzes in a quarter with N% correct or higher, that sort of thing).

Keep the Quarterly PL/SQL Championship

One could argue that there will no longer be enough quizzes in a quarter (12 weekly vs roughly 60 daily) to establish clearly who should participate in the championship. I was thinking about switching to a semi-annual (every 6 months) championship, but that complicates matters in our backend (support for a new frequency) and I don't really want to give players any fewer reasons to think about and visit the site.

We will probably adjust the rules around what it takes to qualify for the championship. And we will continue to play at a single time, to ensure the integrity of the competition.

Add a New Annual PL/SQL Championship

We are adding annual championships for SQL and Logic in 2014. We will do the same for PL/SQL, maybe starting in 2014 or wait until 2015.

Still sorting out the rules for participation. Maybe we will "loosen" things up and make it an "open" contest: anyone can play!Or have an open qualifier: take three quizzes (everyone at the same time), top 50 play in the annual championship.

Set Up More Tests
We recently rolled out the new Tests feature, which currently gives you the ability to take a past PL/SQL Quarterly Championship under the same conditions as the original players.

We will add more tests with specific feature area foci, such as a test on dynamic SQL or bulk processing. These will consist of multiple quizzes (not from those already played) that are designed to test how thoroughly you understand a particular area of functionality, and will include a mix of code-based and word quizzes.

Build the Community

I spend so much time writing quizzes, I don't have enough time to more fully develop the community side of the PL/SQL Challenge. I would like to start highlighting player accomplishments (Player of the Year, Reviewer of the Year, etc.), as well as provide better-organized and fully-realized utilities and reusable code.

And more generally I want to make the site less about/from me and more about featuring the knowledge and experience of PL/SQL experts all around the world!

Participants in the Q3 2013 PL/SQL Championship

The following players will be invited to participate in the Q3 2013 championship playoff. The number in parentheses after their names are the number of playoffs in which they have already participated.

Congratulations to all listed below on their accomplishment and best of luck in the upcoming competition!

We currently plan to hold the championship on 7 November (again, at a single time world-wide), and are waiting for confirmation from players.

See the FAQ for an explanation of the three ways a player can qualify for the playoff.

Name	Rank	Qualification	Country
swart260 (5)	1	Top 25	Netherlands
Rakesh Dadhich (3)	2	Top 25	India
Oleksiy Varchyn (0)	3	Top 25	Norway
Stelios Vlasopoulos (8)	4	Top 25	Belgium
Ajaykumar Gupta (2)	5	Top 25	Singapore
Janis Baiza (7)	6	Top 25	Latvia
mentzel.iudith (11)	7	Top 25	Israel
Jerry Bull (9)	8	Top 25	United States
Niels Hecker (12)	9	Top 25	Germany
Frank Puechl (2)	10	Top 25	Germany
Siim Kask (11)	11	Top 25	Estonia
Viacheslav Stepanov (10)	12	Top 25	Russia
Justin Cave (9)	13	Top 25	United States
dannyg64 (2)	14	Top 25	United States
Peter Schmidt (4)	15	Top 25	Germany
Andrey Zaytsev (0)	16	Top 25	Russia
Hamid Talebian (0)	17	Top 25	Netherlands
Jeroen Rutte (5)	18	Top 25	Netherlands
Michal Cvan (9)	19	Top 25	Slovakia
Milibor Jovanovic (3)	20	Top 25	Serbia
Zoltan Fulop (5)	21	Top 25	Hungary
Pavel Vorontsov (0)	22	Top 25	Russia
Frank Schmitt (6)	23	Top 25	Germany
_tiki_4_ (4)	24	Top 25	Germany
Ivan Blanarik (6)	25	Top 25	Slovakia
Tony Winn (3)	32	Wildcard	Australia
Giedrius Deveikis (3)	38	Correctness	Lithuania
Denis Ivin (0)	42	Correctness	Russia
Tobias Stark (2)	56	Correctness	Germany
Martin_Scholz_Berlin_Berlin (0)	57	Correctness	Germany
james su (6)	84	Wildcard	Canada
Ingimundur Gudmundsson (1)	87	Correctness	Norway
Thierry Poels (5)	92	Correctness	Belgium
richb (0)	133	Correctness	United States
Dan Kiser (4)	223	Correctness	United States
Telmoc (0)	224	Correctness	Portugal
Upendra Motamarri (0)	316	Correctness	India

How One Team Enjoys the PL/SQL Challenge

A very nice thing about my announcement over the weekend regarding cheaters is that it prompted several players to write to me about how much they have enjoyed the PL/SQL Challenge.

Here's the best story I got - it really made my day!

Thank you very much for this great project. I love the challenge and learn (almost every day) new aspects of PL/SQL.

I thought you might like to hear how we "celebrate" the PL/SQL Challenge at our company.

 

We are currently 6 developers using PL/SQL and playing the PL/SQL Challenge.

 

We made our own trophies:

• Bronze for the leader in the previous week
• Silver for highest ranking player in the last month
• And gold for the best player in last quarter

Here's a picture of our quarterly trophy:

 

It's always a fun and funny moment when the previous owner of the trophy presents it to the new winner. 

 

How wonderful and entertaining! Thanks so much, Peter,for sharing this with me.

 

Do you have a fun story about the PL/SQL Challenge in your life and/or your job? Please let us know and we will post it on the blog!

 

Steven

Sad Day for the PL/SQL Challenge: Cheaters Removed

Since the early days of the PL/SQL Challenge, we have been aware of the possibility of cheating by players. In response, we developed a set of tools to analyze player data to identify patterns of answer submissions that could reflect one or another form of cheating (such as a single person having multiple accounts, or multiple people colluding to achieve high scores).

We have in the past applied these tools to identify players who answer too quickly, and made adjustments to their scores accordingly. When we apply the adjustment, we notify the players that:

It is certainly quite possible that a person answering so quickly (and correctly) is cheating by taking the quiz under a different account, figuring out the correct answers, and then submitting the answer under their "real" account. It is also possible that they knew that subject very well or simply guessed. Rather than automatically reject such answers, we analyze player patterns over a longer period of time, usually no less than two weeks. We then make adjustments to the timings and ranks of those players who answer, cumulatively, in so short an amount of time that there is no way to distinguish their pattern of play from someone who would be cheating. 

Today, it is my distinct non-privilege to announce that I have removed from the website three players who I believe have colluded over many quarters to take a whole bunch of the top prizes in the quarterly PL/SQL Championships. The players are (with their championship history under their names):

Frank Schrader

Q3 2010:12th, Q4 2010:30th, Q1 2011:1st, Q2 2011:5th, Q3 2011:1st, Q4 2011:1st, Q1 2012:13th, Q2 2012:3rd, Q3 2012:2nd, Q4 2012:4th, Q1 2013:2nd, Q2 2013:22nd

Dieter Kowalski

Q1 2012:21st, Q2 2012:8th, Q4 2012:16th, Q1 2013:24th, Q2 2013:16th

Konrad Schmidt (kowido)

Q1 2011:26th, Q2 2011:9th, Q3 2011:17th, Q4 2011:21st, Q1 2012:4th, Q2 2012:1st, Q3 2012:9th, Q4 2012:2nd, Q1 2013:1st, Q2 2013:15th

As you can see, two of our consistent champions dropped dramatically in ranking when in the Q2 2013 championship everyone played at the same time.

After I notified all three players of my determination and asked for a response, all three "people" immediately stopped playing. Only Frank even replied to my request and he protested his innocence. Unfortunately, it was not a convincing protest. The bottom line is that there is no way to distinguish their pattern of play from someone who would be cheating. 

Frank and Konrad cumulatively won $2800 in prizes on the PL/SQL Challenge site. This is, of course, a source of extreme frustration for me....but what can you do?

Well, here's what we can do: all rankings have been recalculated after these players' removal. We therefore have in many cases new winners for the championships. I am sorry that we will not be able to issue prizes to these new winners, but at least you will be able to print off and display your certificate of achievement - and these new achievements become a part of your profile and history on the PL/SQL Challenge website.

And - do I really need to say this? - let this be a warning to other players who are cheating or contemplating such: we will continue to enhance and apply our tools to root our cheaters, remove them from the site, and announce their crimes to the world.

We may also make our tools available on the website itself, so that any players can run the analysis and see if they can uncover cases of potential cheating to report to us.

New Weekly Quiz on Database Design

Since April 2010, the PL/SQL Challenge has offered daily, weekly and monthly quizzes on Oracle PL/SQL, SQL, deductive logic and Oracle Application Express. Oracle technologists have submitted over 740,000 answers to these quizzes. Hundreds have raved about how much they have learned, how much fun it is to compete (or not, as you choose!)....

This website is one of my proudest achievements, but I sure would love to have more of my developer and DBA friends around the world using the site.

So I am excited to announce a new weekly quiz on Database Design, which will start on 5 October.

Relational databases form the backbone of thousands, if not millions, of applications around the globe. A key part of building these applications is designing and implementing the data structures they use. Proper table design can mean the difference between a scalable, high performing database that is a joy to query and an unscalable mess that makes your brain melt.

Given the importance of databases, understanding good data modelling techniques and physical implementation methods are essential skills for architects, database administrators and developers creating database applications.

Building on the SQL and PL/SQL quizzes already available at the PL/SQL Challenge, the weekly Database Design Quiz kicks off on 5 October to help you build these skills. The quiz will cover many areas of database design, from logical design all the way to physical database design, including topics such as:

• Normalization - ensuring you have high quality data
• Referential integrity - saving you the time and effort of writing your own constraints
• Indexing - enabling you to write fast and efficient queries

Whether you're an experienced data modeller or completely new to relational databases, the weekly Database Design Quiz offers you the opportunity to both learn new approaches and show off your expertise. It will teach techniques that you can use to improve the quality for your work and impress future employers with your achievements.

The person who has made this quiz possible is Chris Saxon, a long-time player on the PL/SQL Challenge. Chris is a database technologist with 10 years experience designing and building Oracle database applications. He currently works as the Data Architect for the airline Flybe, a role which sees him creating the data structures for the flybe.com database and the company's enterprise data warehouse. He also runs the blog www.sqlfail.com, a project to explain database concepts and other topics of interest using just SQL and PL/SQL. While not thinking about data, his spare time is filled chasing after his daughter Isabelle, born in January this year.

I have, by the way, seen pictures of Isabelle. She is beautiful!

But Chris is so devoted to his craft and so interested in helping others that he is going to give up precious time with his daughter to create and manage the quizzes.

So play the quiz! Every week! Starting 5 October (this Saturday).

If you have not yet visited the PL/SQL Challenge, it's easy to register and entirely free. Check it out!