Lord of the Flies, by William Golding

This book touches a very uncomfortable subject for me: the mindless, visceral hive mind of the crowd. There is nothing more horrible, I find, that being powerless in front of a mob of people united by only their stupidity and fear. Lord of the Flies is the archetypal book about this subject. It tells the story of a bunch of British kids stranded on a small island without any adult supervision. They create a parody of human society which ultimately fails horribly towards the end.

The book is short, but to the point. Sections of it are almost unbearable to read, not because it features monsters or supernatural creatures, but because you feel deep inside that it is the truth, that these things happen and that they do because of something deep inside each of us.

The only failing of the book, I feel, is that Jack and Roger are portrayed as classical psychopaths and it is clear from the beginning that one cannot empathise with them. A slightly longer story that would have made the effort to make these characters slightly likeable would have had an even deeper impact. In that case, I fear, the book would have become completely unbearable. People need their illusions about the society around them; shattering them completely would not do.

This book is a must read for any student of human psychology and one of the best books to reference at parties to make you look smarter than you are :-) I've actually read the book because I was doing that too much, but had only seen the movie. I wonder if I should get other works from William Golding, since I liked this one so much.

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SET versus SELECT in T-SQL

Let's start with an example:

DECLARE @SiteId INT
SELECT @SiteId=isnull(SiteId,0) FROM Orders WHERE OrderID=15
UPDATE Order_Sites SET SiteID=@SiteId

Can you spot the problem? What if SiteID in Order_Sites is not nullable? What if there is no order with OrderId 15?

That's right, when you select into a variable, you must be certain that the query returns any rows, otherwise the variable will not be set at all.

The solution is to add another operation that sets the value correctly. Here are three possible options:

• Set @SiteId to 0 before the select.
• Set @SiteId to isnull(@SiteId,0) after the select and simplify the select to not contain the isnull.
• Use the select as an argument of the isnull operation:

  SET @SiteId= isnull((select SiteId from Master_orders where OrderID=-1),0)

  Yes, you can do that.

Either way, always pay attention to this gotcha in using SQL.

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Have children, please!

"Oh, no! Siderite's blog has been hacked", you will think immediately. People who know me know how I feel about having children, and that is: I don't feel anything. I seem to lack that inner feeling that makes people procreate for no good reason. And while I am at the subject, I do not deny the existence of this feeling in the world and I don't believe most people are like described below, at least I hope so, but it just hit me that so many times, people have said something and meant another. I will elaborate. Stay assured, my blog was not hacked yet.

You know those dreams we have when we are young? We will get rich and famous, we will find true love, we will be the best at what we do, we can do anything if we want, we can quit anytime (but we don't want to), we will always have time to lose weight and go to the gym, etc. We actually believe those things will happen for most of our youth and early adulthood and some of us actually do something about it, while the most just expect it will happen if they wait long enough.

Well, after a while, reality hits home and we understand that we actually cannot do all of those things, maybe none of them and that our life will not get any better than it is on its own. Some people, at this moment in life, start thinking about children. This way they can delay losing hope by passing it on to their children. That's why many parents are disappointed with their offspring, not because they actually thought their children were special, but because they forced themselves to believe it. In the end, they spawn other normal people, just like them.

You may feel that I am too much of an asshole saying these things, even more than usual, but I don't think so. You see, the assholes are people who spontaneously start advising you to have children, like they already have or plan to. When they say that, they are saying "For a moment now, I thought you might be better than me and I felt a little threatened. Have some children, please, so I can feel better about myself". Have you ever heard the one about children "fulfilling you"? Do I look half full to you? My life does have meaning and I am quite happy with it. I don't need children, therefore I am not having any. If I look unhappy, it may be because I still have hopes for myself and I still believe I can do better. I get disappointed in myself because I expect a little more from me.

I had to write this post because the only times I actually considered having children for more than one second was when I was depressed for not doing something as well as I wanted or when not having time to fulfil ALL of my dreams. I just realised that. There was never a content, happy time in my life when the thought ever crossed my mind.

Now I know that alphish or hormonal males and females do naturally feel the need to have children. I understand the overall need for our species to procreate (although, not right now, when we are too many to fart without a human nose having to smell it). I also don't begrudge or disrespect people having children (as long as they keep them out of my face). However, think long and hard before you tell someone to have children. What is actually the reason you are saying that? Aren't you a bit of an asshole, even if it were any of your business?

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Careful when reusing Javascript RegExp objects

I had this operation on a Javascript object that was using a complex regular expression to test for something. Usually, when you want to do that, you use the regular expression inline or as a local variable. However, given the complexity of the expression I thought it would be more efficient to cache the object and reuse it anytime.

Now, there are two gotchas when using regular expressions in Javascript. One of them is that if you want to match on a string multiple times, you need to use the global flag. For example the code

var reg=new RegExp('a',''); //the same as: var reg=/a/;
alert('aaa'.replace(reg,'b'));

will alert 'baa', because after the first match and replace, the RegExp object returns from the replace operation. That is why I normally use the global flag on all my regular expressions like this:

var reg=new RegExp('a','g'); //the same as: var reg=/a/g;
alert('aaa'.replace(reg,'b'));

(alerts 'bbb')

The second gotcha is that if you use the global flag, the lastIndex property of the RegExp object remains unchanged for the next match. So a code like this:

var reg=new RegExp('a',''); //same as: /a/;
 
reg.test('aaa');
alert(reg.lastIndex);
 
reg.test('aaa');
alert(reg.lastIndex);

will alert 0 both times. Using the global flag will lead to alerting 1 and 2.

The problem is that the solution to the first gotcha leads to the second like in my case. I used the RegExp object as a field in my object, then I used it repeatedly to test for a pattern in more strings. It would work once, then fail, then work again. Once I removed the global flag, it all worked like a charm.

The moral of the story is to be careful of constructs like _reg.test(input);
when _reg is a global regular expression. It will attempt to match from the index of the last match in any previous string.

Also, in order to use a global RegExp multiple times without redeclaring it every time, one can just manually reset the lastIndex property : reg.lastIndex=0;

Update: Here is a case that was totally weird. Imagine a javascript function that returns an array of strings based on a regular expression match inside a for loop. In FireFox it would return half the number of items that it should have. If one would enter FireBug and place a breakpoint in the loop, the list would be OK! If the breakpoint were to be placed outside the loop, the bug would occur. Here is the code. Try to see what is wrong with it:

types.forEach(function (type) {
    if (type && type.name) {
        var m = /(\{tag_.*\})/ig.exec(type.name);
        // type is tag
        if (m && m.length) {
            typesDict[type.name] = m[1];
        }
    }
});

Click here to see the answer

The problem (most likely a bug in FireFox) is that instead of recreating the regular expression in the loop at every iteration, it would cache it instead and use it as a global regular expression. Remove the 'g' and it works. Use the new RegExp(...) notation and it works. Even place a breakpoint in the loop (thus disabling the optimization built in FireFox) and it works. As it is it will attempt to match every second string from the position of the last matched string on.

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THE PLEASURES OF STATISTICS: The Autobiography of Frederick Mosteller.

I was looking for autobiographies, since I liked quite a few of them lately and I felt like more, and so I got two. One is interesting because it is finally in print after 100 years since the author's death. I am talking about the first volume of Mark Twain's biography. However, I really could not make myself read it: the language was so pompous and the content so lame that I felt pain trying to.

Not so the second book, which seemed even more unlikely for me to like it: THE PLEASURES OF STATISTICS: The Autobiography of Frederick Mosteller, but which I did. It started with a few projects that Fred Mosteller participated in, explaining the day to day concerns and situations of a statistician while working on them. I thought at first that the book is going to be all like this, so after about a third I was about to abandon the read. You see, it was all very interesting from a professional statistician's point of view, but I wanted the more personal viewpoint of the man. And so I got it. Suddenly the book changed pace and went with the early life and education of Mosteller. The end of the book again covered some cases of work, but this time with a personal touch that explained the motivation behind the acts. And finally, the editor's epilogue, written from testimonies of friends and colleagues.

In this review, a Theodore M. Porter argues that the autobiography was flawed, as it covered little of his family life and couldn't reconcile the different viewpoints that appeared in the book, like the scientific and personal. But I disagree. The autobiography was unfinished and I guess the editor did the best he could with what he had, but it couldn't have been a lot different from what Mosteller himself intended. You start with the actual work: statistics, explained in layman's terms, then you continue with the actual man, explaining the origins and education, then you get back to statistics, but examining the work from the personal viewpoint of the man described. Yes, he could have written about his family more, but it wouldn't have been about statistics. The little he does write about his wife is about how supportive she was throughout his career. And yes, the tone of the book is a bit clinical, but this is how the writer actually thought like; he was a scientist in the true sense of the word and I liked this book exactly because it made me understand how such a man thinks and feels.

Even more than the structure of the book and the insight in the mind of a conscientious and brilliant scientist what I liked most is the peek at the world in the middle of the 20th century and how strikingly different it was from what we see today. The concerns of a teacher towards the best method to get his students to understand and like the subject, the way people were getting together to solve problems and worked for years on a book or bunch of science papers, the way academia was also supportive, not only political, and most of all, to see how people can be both brilliant and empathic, both clinical in science and warm in person.

I wouldn't recommend this book to everyone. I had a hard time reading it to the end and paying attention to every bit. Nor should one study it like a school manual, because as far as I see, the book is about a man's soul and you only have to understand and feel that. Whether it is because of my autobiography fad or because I resonated with the man or for some other reason, the bottom line is that I enjoyed reading the book. Maybe you will too.

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Hosting chess games in your blog posts

Finally I have found the chess game viewer I wanted in order to publish my own PGN games in the blog! The name is Chess Tempo PGN Viewer and it is well written, fast, supports annotations and variations and is very configurable. Most of all, it is all Javascript (sorry for the occasional Java prompts. I almost caved in and did what I swore I wouldn't ever do: have Java applets in my blog).

Please tell me if you have issues with the new chess viewer.

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The Stonewall attack chess opening

Luckily for me, some chess videos are for beginners like me. Here is one from OnlineChessLessons, describing a simple, clear opening called The Stonewall Attack. After watching the video I played a game with my trusted Nokia phone and managed to create a game starting with this opening. I then analysed it using chess engines Houdini and Rybka and annotated it manually. Check it out, including the variations.

Video first:

Make sure you also follow the article attached to the video.

And now my game:
[Event "29/10/2011 1:08:49 pm"]
[Date "29/10/2011"]
[White "Siderite"]
[Black "Nokia Easy5"]
[Result "1-0"]
[ECO "D05"]
[Opening "Colle"]
[Variation "5.c3 Nc6 6.Nbd2 Bd6 7.O-O O-O"]
[TimeControl "600"]
[Termination "normal"]
[PlyCount "59"]
[WhiteType "human"]
[BlackType "computer"]


1.d4 e6 2.e3 d5 3.Bd3 Bd6 4.f4 Nf6 5.Nd2 O-O 6.Ngf3 c5 7.c3 Nc6 8.O-O c4 9.Bc2 Ng4
{At this point, the engines suggest Bxh7, a classic sacrifice.}
10.Qe2
{However, I moved the queen to defend e3.}
( 10.Bxh7+ Kxh7 11.Ng5+ Kg8 12.Qxg4
{This variation wins the h7 pawn, but moves away from the spirit of the original game.}
12...Qf6 13.e4 ) 10...f5
{At this point, engines suggest Ne5, followed by knight exchange from black.}
11.h3
{I chose to shoo the knight away, but weakening g3, where the knight would love to come later.}
( 11.Ne5 Ngxe5 12.dxe5 Be7 13.b4 ) 11...Nf6 12.Ne5 Qa5 13.g4 fxg4 14.hxg4 Qb6
{engines would want me to attack the knight on f6 before moving the rook out.}
15.Rf2 ( 15.g5 Bxe5 16.dxe5 Ne8 17.Kg2 g6 18.b3
{Engines decide to try a queen side attack as well, in order to weaken the black pawn chain. I was not interested in that.}
) 15...h6
{engines suggest attacking the rook and with Ng6, which is a natural attacking move and a lovely outpost.}
16.Rh2 ( 16.Ng6 Rf7 17.g5 Nh7 18.Qh5 Ne7 19.Nxe7+ Rxe7 20.gxh6 Nf8 21.Rg2 Qc7 22.Qg5
{However at this point the game moves into queen side attacks and a slower attacking pace.}
) 16...Ne7 17.g5 hxg5 18.fxg5 Bxe5 19.dxe5 Nd7
{engines suggest now a beautiful move: Rh8, followed by a munching of black pieces or/and mate. Make sure you check out the variation.}
20.Nf3 ( 20.Rh8+ Kf7 ( 20...Kxh8
{Taking the rook leads to a quick mate.}
21.Qh5+ Kg8 22.Bh7+ Kh8 23.Bg6+ Kg8 24.Qh7# ) 21.Qh5+ g6 22.Bxg6+ Nxg6 23.Qh7+ Ke8 24.Qxg6+ Kd8 25.Rxf8+ Nxf8 26.Qf6+ Ke8 27.Nf3
{Try this variation on a chess engine to see it to the end. White is only one pawn up, but it is a passed one. The king is safe as well.}
) 20...Rb8 21.g6 Nf5 22.Rh3 Nh6 23.Kh1
{I felt like the pin on e3 was annoying and stopping me from using the black bishop. The engines recommend moving Qh2 instead, which is much better.}
( 23.Qh2 Nc5 24.Ng5 Ne4 25.Bxe4 dxe4 26.Nh7 Qc7 ( 26...Rd8
{If you wanted to know why black did not move the rook when attacked by the knight, follow this variation through.}
27.Rxh6 Rd1+ 28.Kg2 Qd8 29.Nf6+ Kf8 30.Rh8+ Ke7 31.Qh4 Rd2+ 32.Bxd2 b6 33.a4 Qxd2+ 34.Kh1 Qe1+ 35.Rxe1 Bb7 36.Rxb8 Bc8 37.Rxc8
gxf6 38.Qh7# ) 27.Nxf8 Qd8 28.Rxh6 Qg5+ 29.Kf2 Qxh6 30.Qxh6 gxh6 31.Nh7
{At this point white is a knight up, but what a boring continuation.}
) 23...Nf5 24.Qh2 Ng3+
{Engines suggest I move the king and concentrating on the attack, but I took the knight with the rook.}
25.Rxg3 ( 25.Kg1 Qxe3+ 26.Bxe3 Ne2+ 27.Kg2 Nf4+ 28.Bxf4 Rf5 29.Rh8# ) 25...Re8 26.Qh7+ Kf8 27.e4
{At this point, a mate in 8 is found.}
27...Qc7
{But with this move, mate will happen in 4.}
28.Bg5 Nf6 29.exf6 Rd8 30.Qh8# 1-0


Enjoy!

P.S. I am currently looking for a method of displaying the game as I want it on the blog: dynamic, with annotation and variation support, preferably something that is not Java and optimally something that reads the PGN from a span and replaces it with a nice looking chess interface. Right now, the usual game engine fails for some reason I need to analyse.

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