1212 chapter databases. © 2005 the mcgraw-hill companies, inc. all rights reserved. 12-2...
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12-2
© 2005 The McGraw-Hill Companies, Inc. All Rights Reserved.
Competencies
Distinguish between the physical and logical view of data
Describe how data is organized
Describe databases
Describe the five data models
Distinguish among the different databases
Recognize strategic database uses & security concerns
12-3
© 2005 The McGraw-Hill Companies, Inc. All Rights Reserved.
Data
Facts or observations about people, places, things, and events
Two ways to view data
Physical view
Logical view
12-4
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Data Organization
Character
Field
Record
File
Database
12-5
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Key Field
Unique identifier
Common examples
Social security number
Driver’s license
Credit card account
12-6
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Batch Versus Real-Time Processing
Batch processing -- later
Real-time processing -- now
Batch Processing
12-8
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Databases
Sharing – one department to another
Security – passwords to access
Less data redundancy
Data integrity
12-9
© 2005 The McGraw-Hill Companies, Inc. All Rights Reserved.
Database Management
DBMS engine
Data definition subsystem
Data manipulation subsystemQuery-by-example
Structured query language (SQL)
Application generation subsystem
Data administration subsystem
12-10
© 2005 The McGraw-Hill Companies, Inc. All Rights Reserved.
DBMS Structure
Hierarchical database
Network database
Relational database
Multidimensional database
Object-oriented database
12-11
© 2005 The McGraw-Hill Companies, Inc. All Rights Reserved.
Hierarchical Database
Fields or records are structured in nodes
Nodes are point connected like branches
One parent per node
Parent has several child nodes
Airlines may use a hierarchical
database
12-12
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Network Database
Hierarchical node
arrangement
Many-to-many
relationship
12-13
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Relational Database
Most flexible
Data stored in table or relation
Tables related via a common data item
Easy to use
12-14
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Multidimensional Database
A variation and an extension of the relational model
Includes a hyper cube
Good for representing complex relationships
Advantages over relationalConceptualization
Processing speed
12-15
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Object-Oriented Database
Works with unstructured data Photographs
Graphics
Audio
Video
Objects contain both data and instructions
12-16
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Types of Databases
Individual or microcomputer database
Company or sharedOperational
User
Distributed
Proprietary
Web database
12-17
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Database Uses and Issues
Strategic usesSpecial type of database called data warehouse
Data mining used to search database
SecurityDatabases are valuable
Protection necessary
12-18
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A Look to the FutureXperanto
Enhancement to searching for data
Access to structured (relational databases) and unstructured data (word processing and spreadsheet files)
12-19
© 2005 The McGraw-Hill Companies, Inc. All Rights Reserved.
Key Terms
application generation subsystem (334)attribute (329)batch processing (330)CGI (Common Gateway Interface) (341)character (329)child node (335)class (338)common data item (337)
common operational database (340)
common user database (340)
company database (339)
data (328)
data administration subsystem (334)
data bank (340)
12-20
© 2005 The McGraw-Hill Companies, Inc. All Rights Reserved.
Key Terms
database (330)
database administrator (DBA) (334)
database management system (DBMS) (333)
data definition subsystem (333)
data dictionary (333)
data integrity (332)
data maintenance (334)
data manipulation subsystem (333)
data mining (342)
data model (334)
data redundancy (332)
data warehouse (342)
DBMS engine (333)
12-21
© 2005 The McGraw-Hill Companies, Inc. All Rights Reserved.
Key Terms
distributed database (340)
entity (329)
field (329)
file (330)
firewall (343)
hierarchical database (335)
hyper cube (337)
individual database (339)
information utility (340)
key field (330)
logical view (328)
many-to-many relationship (335)
method (338)
microcomputer database (339)
12-22
© 2005 The McGraw-Hill Companies, Inc. All Rights Reserved.
Key Terms
multidimensional database (337)
network database (335)
node (335)
object (338)
object-oriented database (335)
one-to-many relationship (335)
online processing (331)
parent node (335)
physical view (328)
pointer (335)
primary field (330)
processing rights (334)
proprietary database (340)
query-by-example (334)
12-23
© 2005 The McGraw-Hill Companies, Inc. All Rights Reserved.
Key Terms
real-time processing (331)
record (330)
relation (336)
relational database (336)
shared database (336)
structured query language (SQL) (334)
Web database (341)
12-24
© 2005 The McGraw-Hill Companies, Inc. All Rights Reserved.
FAQs
What is data? Name the different types of data.
What is the difference between a physical and a logical view?
What is a key field?
What is a relational database?
What are the five classifications of databases?
What is data mining?