June 2010
Intermediate to advanced
328 pages
7h 51m
English
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Antipattern: Solve a Complex Problem in One Step
SQL is a very expressive language—you can accomplish a lot in a single query or statement. But that doesn’t mean it’s mandatory or even a good idea to aim to solve every problem in one line of code. Do you have this habit with any other programming language you use? Probably not.
Unintended Products
One common consequence of producing all your results in one query is a Cartesian product. This happens when two of the tables in the query have no condition restricting their relationship. Without such a restriction, the join of two tables pairs each row in the first table to every row in the other table. Each such pairing becomes a row of the result set, and you end up with many more rows than you ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.