January 2021
Intermediate
240 pages
5h 32m
Japanese
Content preview from 図解まるわかり データベースのしくみ
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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.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.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.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.
166
本のレビューサイトのテーブルを設計
する例④ ～テーブル・カラムを整える～
5-19
必要なテーブルやカラムが定まったら、5-14 で解説したようにカラム
に割り当てるデータ型や制約、属性を決定します。さらに5-15 のように
テーブルやカラムの名前を整えると、図5-33 のようになりました。
それぞれのテーブルに設けた「id」カラムは他のレコードの値と重複し
ないように主キーとし、自動的に連番を割り当てるようにしました。ま
た、他のテーブルと関連付けるためのIDを格納するカラムは「テーブル
名（単数系）̲id」に統一し、外部キーとしてあります。また、booksテー
ブルの登録日を保存するカラムは、日付が格納されるカラムであることが
わかるように「◯◯◯̲at」としてあります。
以上で本のレビューサイトのテーブルを設計することができました。こ
こでは円滑に設計を進めたり、効率のよいデータ構造を理解するために、
いくつかのステップに分けて設計手順を紹介しましたが、
1
2
こともあるでしょう。
ここで紹介した手順や図は、あくまでテーブル設計の手段の1 つですの
で、基本が理解できるようになったら、プロジェクトの規模や作成するシ
ステム、自身のスキルに応じて使い分けるようにしていきましょう。 ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
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.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
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.