August 2024
Intermediate to advanced
392 pages
10h 4m
Japanese
Content preview from 達人に学ぶDB設計徹底指南書 第2版
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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.
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このダブルマスタは、最初に見たときに、むしろどうやったらこのようにマスタ
が二つに分かれるのか、といぶかしく思うかもしれません。実際、普通に設計をし
ている限り、このような不可解な状態には陥りません。実は、ダブルマスタが生じ
る直接的な理由は一つで、それは、もともと別のシステムで利用されていたマスタ
同士が、システム統合によって同じドメインに存在するようになったためです。
たとえば、金融機関や小売業の企業は、それぞれ独自に顧客マスタを管理して
いるでしょう。そしてその企業の内部に限れば、顧客の一元管理は実現できていた
わけです。しかし、近年盛んな企業同士の合併や買収によってシステム統合が行
なわれると、それぞれの企業が管理していたデータも統合の必要が出てきます。
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そうすると、互いに同じような役割を持っているテーブルが複数存在すること
になります。そのとき、きちんとデータを精査してエンティティの統廃合を行なえ
ば、ダブルマスタが生じることはないのですが、それには時間と人手がかかりま
す。データモデルを一新すれば、データベースに接続している既存アプリケーショ
ンにも改修が及ぶでしょう。そのようなわけで、往々にしてこの部分のタスクに手
を抜いて、既存のエンティティを並べただけ、という名ばかりの統合が行なわれる
ことも珍しくないのです。
このようなデータ精査の作業を、デー
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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.