Database Modeling & Design Fourth Edition- P12 ppsx

... a primary key arises in the context of database design. Often, each row of a table is uniquely identified by the values contained in one or more columns designated as the primary key. Objects ... workflows that are followed by people and organizations, since these are more use- ful for the logical design of databases. 3.2.1 Activity Diagram Notation Description Activity diagrams include...

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... Database Modeling & Design: Logical Design Fourth Edition TOBY TEOREY SAM LIGHTSTONE TOM NADEAU AMSTERDAM • BOSTON ... Cerra Publishing Services Manager Simon Crump Editorial Assistant Asma Stephan Cover Design Yvo Riezebos Design Cover Image Getty Images Composition Multiscience Press, Inc. Technical Illustration ... CA 94111 This book is printed on acid-free paper. © 2006...

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... the approach to designing large relational databases by reducing the Teorey.book Page 6 Saturday, July 16, 2005 12:57 PM 1.2 The Database Life Cycle 3 1.2 The Database Life Cycle The database life ... requirements Physical design Logical design Implementation Teorey.book Page 4 Saturday, July 16, 2005 12:57 PM 1.2 The Database Life Cycle 5 b.View integration. Usually, when the d...

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... shown here. (a) Figure 2.3 Conceptual data modeling notations ER model constructs using the Chen notation ER model constructs using the "crow's-foot” approach [Knowledgeware] Department Division ... applied to Department to designate the start date for that department. Alternatively, it could be applied to Employee as an attribute for each Employee instance, to designate the em...

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... Figure 3.1 shows generalization from the Sedan class to the Car class. 3.1.2 Class Diagrams for Database Design The reader may be interested in the similarities and differences between UML class diagrams ... 40 CHAPTER 3 The Unified Modeling Language (UML) association can indicate mandatory existence, while the other end may use ... attention to capturing primary key information in Figu...

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... of the descriptor attribute “job- title” could represent the consolidation of two views of the database one based on an individual as the basic unit of personnel in the organi- zation, and another ... characteristics within those classifications. 4.4.4 Merging and Restructuring of Schemas The fourth step consists of the merging and restructuring of schemas. This step is driven by the go...

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... as a job ticket, and the job ticket moves to scheduling. We need to determine the grain before designing a schema for the estimating data mart. The grain should be at the most detailed level, ... system, and this level of detail is also potentially valuable for the data warehouse users. The next design step is to determine the dimensions. Looking at the estimating detail, we see that the as...

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... automatically select, maintain, and use the ASTs. Thus, an OLAP system effectively does some of the design work auto- matically. This section covers some of the issues that arise in building an OLAP ... point in the tree. The calculations of Equation 8.4 are illustrated with a small example. An actual database would yield much larger numbers, but the concepts and the equations are the sam...

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... of HRU is O(k2 2d ). HRU runs in time exponentially relative to the number of dimensions in the database. The Polynomial Greedy Algorithm (PGA) [Nadeau and Teorey, 2002] offers a more scalable ... adaptable and improves over time. The comple- mentary nature of these two approaches has influenced our design plan in Figure 8.14, as indicated by Queries feeding back into View Selection. 8.2....

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... amounts of data in an efficient and user-friendly manner. Dimensional data modeling is the approach best suited for designing data warehouses. OLAP is a service that overlays the data warehouse. ... values. Roll- up and drill-down operations are typical. OLAP systems automatically perform some design tasks, such as selecting which views to materialize in order to provide quick response ti...

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