PATTERNS OF DATA MODELING- P43 docx

... areas. The generic diagram model provides a starting point for various kinds of diagrams such as data structure diagrams, data flow diagrams, state diagrams, and equipment flow diagrams. I have used ... that cause changes of state. State diagrams are often used for control and managing user interaction. They are also helpful for enforcing business policies and constraining data — th...

Ngày tải lên: 05/07/2014, 06:20

... data. An application may also have a database that developers populate apart from Eclipse. If you reverse engineer the database, the resulting model can appear to be incomplete. Ideally the database ... I was reverse engineering the database of a commercial product and was perplexed. The resulting model had many disconnected entity types with only a smattering of relationships. I could...

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... and there is special data to collect for them, such as sales data, credit information, and discount schedules. You could use softcoding (see Chapter 13) to capture customer data, but an alternative ... ad- dress. 10.4 Asset An Asset is something of value (Figure 10.7, Figure 10.8). An OwnedAsset is an asset that is owned outright. A RentedAsset is the use of an OwnedAsset for some tim...

Ngày tải lên: 05/07/2014, 06:20

Ngày tải lên: 05/07/2014, 06:20

... Modeling Notation 1 1.3 What Is a Pattern? 2 1.4 Why Are Patterns Important? 3 1.5 Drawbacks of Patterns 4 1.6 Pattern vs. Seed Model 4 1.7 Aspects of Pattern Technology 5 1.8 Chapter Summary 6 Bibliographic ... Summary 89 Bibliographic Notes 89 References 90 Chapter 7 Summary of Templates 91 Part II: Antipatterns 95 Chapter 8 Universal Antipatterns 97 8.1 Symmetric Relationship Ant...

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... expertly building data models. This book focuses on databases and not on programming, because most commercial software is built around a database. The database representation (the data model) sets ... scope, and set the xiv Preface key abstractions in the software. These tasks revolve around models and often data mod- els. The skillful use of patterns is intrinsic to building qualit...

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... chapter starts with a discussion of models and then introduces the topic of patterns. 1.1 What Is a Model? A model is an abstraction of some aspect of a problem. Most software models are expressed as ... combinations. Patterns provide a higher level of building blocks than modeling primitives. Patterns are prototypical model fragments that distill the knowledge of experts. •...

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... Software Architecture: A System of Patterns. Chichester, United Kingdom: Wiley, 1996. [Chen-1976] PPS Chen. The entity-relationship model—toward a unified view of data. ACM Transac- tions on Database ... Vlissides. Design Patterns: El- ements of Reusable Object-Oriented Software. Boston, Massachusetts: Addison-Wesley, 1995. [Hay-1996] David C. Hay. Data Model Patterns: Conventions...

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... the sequence of types in the levels of the hierarchy. • Simple tree. Restricts nodes to a single tree. Treats nodes the same. Use when tree de- composition is merely a matter of data structure. • ... context. Figure 2.11 shows an excerpt of this book’s file structure where I have kept old copies of files from reviews. File names are unique within the context of their directory....

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... branch nodes. A Tree is a hierarchy of nodes and has one node as the root. A particular node may, or may not, be the root. You need not show Tree in a use of the tem- plate. A Node is either ... nodes each of which, in turn, can be a leaf node or a further branch node. Figure 2.18 adds the constraint that a tree cannot have any cycles. (See Section 2.2.1 for an explanation of cycles.)...

Ngày tải lên: 05/07/2014, 06:20