文档介绍：Unit 5 Methodologies for Conceptual Design
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本單元目的
提出 refinement primitives 用來將一初始之 schema 轉為結果所需之 schema.
Schema transformation-
以漸進修改方式找 schema
Primitive transformation
用難以再簡化的動作單元做轉換工作
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Outline
Primitives for Conceptual Design
Top-Down Primitives
Bottom-up Primitives
Strategies for Schema Design
Top-down Strategy
Bottom-up Strategy
Inside-out Strategy
The Mixed Strategy
Criteria for Choosing among Concepts
Inputs, Outputs, and Activities of Conceptual Design
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Schema Transformation
From starting schema transforming into resulting schema.
在 starting schema 中使用的名稱, 在觀念上要對應至 resulting schema.
例: PLACE 轉為 CITY, IN, STATE
在 resulting schema 中的邏輯關係(包括 entities, relationship…)必須由 starting schema 繼承而來.
例: PERSON 和 PLACE 之間的關係保持到 resulting schema.
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An Example of Schema Transformation
初始架構
結果架構
轉換
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Top-Down Primitives
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Top-Down Primitives
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Examples of Top-Down Primitives
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Example of Top-Down Primitives
MANAGER 原來藏在
DEPARTMENT 裡
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Example of Top-Down Primitives
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