Database Modeling & Design Fourth Edition- P55 pps

... K -> MNQ (or K -> MNPQ) First, merge (2) and (3) for superkey rules 1 and 2 3. N -> KP (or N -> K) Steps 4 and 5: 1. J -> KL Candidate key is J (BCNF) 2. K -> MNPQ and N -> ... -> KLMNP First, reduce by eliminating MNP since K -> MNP 2. K -> MQNP Second, reduce by eliminating P since N -> P 3. N -> KP End of Step 2 and consolidation in Step 3: 1. J -> ....

Ngày tải lên: 05/07/2014, 05:20

... 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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... software design- ers. Database designers, on the other hand, do not generally deal with class operations; however, the attributes are of paramount importance. The needs of the database designer ... discussing database design issues. UML class diagrams capture the structural aspects found in database schemas. UML activity diagrams facilitate discussion on the dynamic processes invo...

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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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... 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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... successful at communicating design issues. 3.4 Summary The Unified Modeling Language (UML) is a graphical language that is currently very popular for communicating design specifications for soft- ware ... popular for communicating design specifications for soft- ware and in particular for logical database designs via class diagrams. The similarity between UML and the ER model is sho...

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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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... computer screen. This has happy conse- quences for the end user and database designer in terms of developing a mutual understanding of the database contents and formally document- ing the conceptual ... entities and relationships. Entity clustering is potentially useful for designing large databases. When the scale of a database or information structure is large and includes a large num...

Ngày tải lên: 05/07/2014, 05:20