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
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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.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.
16
データベースの特徴
1-2
データベースには、おおまかに登録・整理・検索ができるという特徴が
あります（図1-3）。
データベースには大量のデータを登録することができ、例えば随時商品
データを追加するといったことができます。そしてデータは整理してそれ
ぞれ同じ形式で保存しておくことができます。ケーキで例えるなら「値
段」といったデータを持っていますが、これらを100、100 円、￥100 の
ようにバラバラのフォーマットではなく、100、100、100 のように整頓
された形でデータベースに格納されます。これらは必要に応じて編集・削
除を行うこともできます。
例えば商品ごとの値段をデータベースに登録しておけば、後から
200 円以上の商品だけを取得できますし、売れた商品と日時を保存してお
けば、今日の売上を取得することが可能です。このように格納されている
データをもとにした条件を加えて、欲しい情報を抽出することができま
す。
ショッピングサイトの商品管理には、データベースが使われています。
管理者が商品ごとに商品名、価格、販売開始日、商品画像URL、紹介文な
どの情報をデータベースに登録しています。ショッピングサイト上では、
このデータベースから商品情報を取り出して内容を表示しています。購入
者は、たくさんの商品の中から商品名で検索できたり、価格で絞り込めた ...
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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.
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.