Databases

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Chapter 11
Databases
Professor Michael J. Losacco
CIS 1150 – Introduction to Computer Information Systems
Overview
Chapter
11
Describe How Data is Organized
Define Key Fields
Compare Batch and Real-time Processing
Define Five Common Database Models
Distinguish the Kinds Of Databases
Discuss Strategic Uses and Security Concerns
2/15
Data Organization
Chapter
11
Field
Combination of Related Characters
Characteristics
Name Uniquely Identifies Each Field
Data Type
Size
Record
Group of Related Fields
Key Field
AKA Primary Key
Uniquely Identifies Each Record
3/15
Data Organization
Chapter
11
Table
Collection of Related Records
Each Record Contains Same Fields
Each Field Contains Different Data
Database
Group of Related Tables
4/15
Batch and Real-time Processing
Chapter
11
Batch Processing
Data Collected Over Several Hours, Days, or Weeks
Processed All at Once as a “Batch”
Real-time Processing
AKA Online Processing
Data Processed at Same Time Transaction Occurs
5/15
Databases
Chapter
11
Need
Sharing
Information Readily Shared Between Departments
Security
Users Access Only the Kind of Information They Need
Less Data Redundancy
Redundancy Causes
Inefficient Use of Storage Space
Data Maintenance Problems
Data Integrity
Multiple Sources of Data Lead to Variations
6/15
Databases
Chapter
11
Validation
Comparing Data with Set of Rules
Reduce Data Entry Errors
Enhance Data Integrity
Types
Alpha / Numeric
Range
Completeness
Consistency
7/15
Database Management
Chapter
11
Database Management System (DBMS)
Subsystems
DBMS Engine
Bridges Logical View and Physical Views of Data
Data Definition
Data Dictionary
8/15
Database Management
Chapter
11
Database Management System (DBMS)
Subsystems
Data Manipulation
Query-by-example, SQL
Application Generation
Data Entry Forms
Data Administration
Maintaining Security
Processing Rights
9/15
DBMS Structure
Chapter
11
Models
Hierarchical
One-to-many Relationship
Rigid Structure
Network
Many-to-many Relationship
Flexible and Efficient
10/15
DBMS Structure
Chapter
11
Models
Relational
No Hierarchical Access Paths
Data Elements Stored in Different Tables
Consist of Rows (Records) & Columns (Fields)
Each Row Has Primary Key
Related Tables Must Have Common Field
11/15
DBMS Structure
Chapter
11
Models
Multidimensional
Data Viewed as a Cube Having Three or More Sides
Represent Complex Relationships Between Data
Click Stream
Object-oriented
Stores Data in Objects
Can Contain Both Data and Actions
12/15
Types of Databases
Chapter
11
Individual
Primarily Used by Just One Person
Company
Stored on a Central Database Network Server
Distributed
Not All Data Physically Located in One Place
Accessible Through a Variety of Networks
Commercial
Large Database that Covers a Specific Subject
Access Offered to the Public for a Fee
13/15
Database Uses and Issues
Chapter
11
Strategic Uses
Data Warehouse
Data Mining
Business Directories
Demographics
Business Statistical
Text
Web
14/15
Careers in IT
Chapter
11
Database Administrator
Determine Ways to Organize and Access Data
Maintain Database Security
Back Up System
Bachelor's Degree in Computer Science
Technical Experience
Annual Salary of $67,000 - $98,000
15/15
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