June 2010
Intermediate to advanced
328 pages
7h 51m
English
Content preview from SQL Antipatterns
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Chapter 4ID Required
The creatures outside looked from pig to man, and from man to pig, and from pig to man again; but already it was impossible to say which was which.
George Orwell, Animal Farm
Recently I answered a question that I see frequently, from a software developer trying to prevent duplicate rows. At first I thought he must lack a primary key. But that wasn’t his problem.
In his content management database, he stored articles for publishing on a website. He used an intersection table for a many-to-many association between a table of articles and a table of tags.
| ID-Required/intro/articletags.sql | |
| | CREATE TABLE ArticleTags ( |
| | id SERIAL PRIMARY KEY, |
| | article_id BIGINT UNSIGNED NOT NULL, |
| | tag_id BIGINT UNSIGNED ... |
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
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.