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SQL PROGRAMMING STYLE- P40

SQL PROGRAMMING STYLE- P40:Im mot trying to teach you to program in SQL in this book. You might want to read that again. If that is what you wanted, there are better books. This ought to be the second book you buy, not the first. I assume that you already write SQL at some level and want to get better at it. If you want to learn SQL programming tricks, get a copy of my other book, SQL for Smarties (3rd edition, 2005). | Fonts Punctuation and Spacing C. ODE IS USUALLY set in a monospace font. After more than a century of manual typewriters and decades of punchcards we find that it is actually easier to read code in a monospace font than a proportional font. Punctuation marks get the same spacing as a letter in a monospace font but would be lost in a proportional font. 2.1 Typography and Code Your brain and eyes do not follow code the same way that they follow text process mathematics read maps or look at pictures. In fact there are a lot of individual differences in human brains. Some people like text editors that use colors for various syntax elements in a programming language. Other people get headaches from colored program editors and want to see black-and-white text. Likewise a newspaper that put nouns in red verbs in green and other such things would simply not work. Yet black-and-white maps are much more difficult to read than those with colors. Why This has to do with color perception and how fast you can switch between the left and right halves of your brain. There is a test for brain damage in which the examiner flashes cards with words printed in various colored inks e.g. the word RED written in green ink . The examiner asks the subject for the word or 24 CHAPTER 2 FONTS PUNCTUATION AND SPACING the color and times the responses. The rate is fairly constant over the subject s lifetime so a change is a symptom of some physical or chemical change. Now try reading this phrase Paris in the the Spring. Almost nobody reading this for the first time catches the fact that the word the appears twice. The point is that there is a vertical component to how we read text in chunks of words. Code on a page is read from left to right and from top to bottom with a lot of vertical eye movement that you would not have if you were reading pure text. A few years ago the following posting made the rounds in newsgroups. I am not sure if it is genuinely from Cambridge University but it makes its