Today, I am going to explain logic design process.
Purposes of this article creation
- To be able to create DB tables in MySQL in Ruby on Rails on my own.
- To be able to do logic design.
Logic Design Process
In this case, I will create logical data model for a SNS task management application on Cacoo as a deliverable.
【What is Logic Design?】
- This is performed in order to assume execution in a real system and to avoid database-induced failures.
- Finally, table structures are created from the logical data model.
【Logic Design Process】
- 1.Create CRUD Matrix(CRUD Analysis)
- 2.Create Decision tables
- 3.Code Design
- Thinking about Data Migration(Data Transition)
- Security Design
※Procedures 1 and 2 above are performed to ensure the logicality of the data life cycle.
※「Thinking about Data Migration(Data Transition)」&「Security Design」 will be summarized in a separate articles.
1. Create CRUD Matrix(CRUD Analysis)
- Analyze which tables are used at which stages of the system to ensure that there are no inconsistencies in the data life cycle.
- It can also be used to estimate the number of table accesses.
※Not included in this time.
2. Create Decision tables
- A table that maps system conditions to execution results.
- It contrasts conditions and processes and describes complex conditional judgment.
※Not included in this time.
3. Code Design
Design an appropriate code system for the data to increase development efficiency and maintainability of the system so that it can be used for a long period of time.
【Merits of Code Design】
- Easier team development.
- Improved software maintainability.
【Types of codes used in code design(Example)】
- Sequence Code (Sequential Code)
- Codes that assign consecutive numbers in sequence (sometimes called sequential codes).
- Block Code (Division Code)
- Codes in which the upper digits are divided into several blocks and sequential numbers are assigned within the blocks.
- Digit-by-digit Code
- A code in which each digit of a code is combined with a meaning.
- Mnemonic Code
- A code expressed by inserting letters, numbers, or symbols such as abbreviations that represent information in the code.
- Decimal Code
- A code in which data is divided into 10 parts from 0 to 9 according to the principle of decimal numbers, and the partitioning is repeated for lower groups of data in the same manner.
【Creation of code design documents】 ※Not included in this time.
Deliverables(Logical Data Model)
- URL：※Not included in this time.
References
[Logic Design]
- 「概念・論理・物理データモデルの違いは人によって異なる？データ総研の考え方をご紹介」：https://jp.drinet.co.jp/blog/modeling_dri
- 「データ中心設計(DOA)に基づいたデータモデリング」：https://thinkit.co.jp/article/17291
- 「設計フェイズ別のデータベース設計手順を解説！おすすめのソフト5選」：https://www.acrovision.jp/career/?p=2252
- 「論理設計と物理設計」：https://bleis-tift.hatenablog.com/entry/20090116/1232078002
- 「MySQLでテーブル定義を調べる方法」：https://qiita.com/keb/items/39a2379b894d0489cb07
- 「13.7.5.6 SHOW COLUMNS 構文」：https://dev.mysql.com/doc/refman/5.6/ja/show-columns.html
[Code Design]
- 「コード設計とは何か？用いられるコードの種類とコード設計書に記述する内容を解説」：https://ssaits.jp/promapedia/method/code-design.html
- 「システムの寿命はコードで決まる！」：https://atmarkit.itmedia.co.jp/ait/articles/0606/08/news124.html
- 「コード設計」：https://e-words.jp/w/%E3%82%B3%E3%83%BC%E3%83%89%E8%A8%AD%E8%A8%88.html
Word Explanation
【About Conceptual, Logical, and Physical Data Models】
[Conceptual Data Model] A data model that is independent of the means of implementation and describes the data required by the company and the relationships among the data.
[Logical Data Model] A data model that describes the structure of the data (data structure of the conceptual data model) organized according to the DBMS.
[Physical Data Model] A data model that describes the structure organized to physically store (the data structure of the logical data model).
Summary/What I learned this time
NONE.
