Beginning Database Design (Wrox Beginning Guides) 电子书下载

书名：Beginning Database Design (Wrox Beginning Guides)

I`m a fairly technical person, but my knowledge of databases was superficial, so I decided to read this book. It is billed as suitable for the novice, and therefore should take things slowly and methodically. It feels disjointed and poorly structured. The author seems to jump from one topic to the next. But probably the most significant problem is that the author uses terms and concepts before defining or describing them. I can only imagine how confused a true novice might be when reading some of this. Examples: He talks about Online Transaction Processing and Data Warehousing without really defining them or giving examples that would help the reader understand what they`re used for. On page 10, there is a figure purportedly showing what a relational database model looks like. However, it uses symbols and lines that he does not explain till later in the book. Without explaining the symbols, what good is the diagram? Many places, he talks about normalization before explaining what it is. In one spot where he starts to explain normalization, he writes, "Normal Forms beyond 3rd Normal Form are often ignored and sometimes even 3rd Normal Form itself is discounted." He does not explain what a Normal Form is.It`s just text that will have no meaning at all to the reader. He talks about tables and columns before adequately explaining what they are. In Chapter 3, he covers simple datatypes. First, he explains what a fixed length string is. But in his accompanying diagram, he uses SQL constructs to explain it. The first line of his explanatory diagram is: SQL> select country||`,`||fxcode||`,`||currency As anyone with programming experience could tell you, explaining what a fixed-length string is is pretty straightforward. But for some reason the author ties it to a complex SQL example, even before he has explained anything about SQL itself. I almost gave up on the book, but slogged through to the end. It does get a little more understandable, yet I sometimes struggled to figure out just what the author was trying to convey. I found several mistakes, and there is an awful lot of needless repetition. There seemed to be several cases where the author said things like: It`s probably a bad idea to ever do X, Y, or Z And then explained how to do X, Y, and Z. It also felt like the author did things like: Explain how to do T Note that it was probably a bad idea to do T Explain how to undo T Do yourself a favor and look through the book before buying it. Perhaps you`ll find it more readable than I have.