Database Modeling & Design Fourth Edition- P35 ppsx
Database Modeling & Design Fourth Edition- P35 ppsx
... 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...
Database Modeling & Design Fourth Edition- P2 ppsx
... 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...
Database Modeling & Design Fourth Edition- P4 ppsx
... 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...
Database Modeling & Design Fourth Edition- P7 ppsx
... 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...
Database Modeling & Design Fourth Edition- P11 ppsx
... 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...
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...
Database Modeling & Design Fourth Edition- P17 ppsx
... 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...
Database Modeling & Design Fourth Edition- P37 ppsx
... 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...
Database Modeling & Design Fourth Edition- P38 ppsx
... 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....
Database Modeling & Design Fourth Edition- P40 ppsx
... 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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