Chapter 7

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CIS 429—Chapter 7
STORING ORGANIZATIONAL INFORMATION—
DATABASES
Storing Organizational Information
 Information is everywhere in an organization
 Information is stored in databases
 Database – maintains information about various
types of




objects (inventory)
events (transactions)
people (employees)
places (warehouses)
Relational Database Fundamentals
 Database
 ___________ information
 Database models
 Hierarchical
Rigid tree-like model
 Used in early DB management systems


Network
Lattice structure
 Child records can have many parent records


____________

Uses logically related two-dimensional tables
Relational Database Fundamentals (2)
 Entities, Entity Classes, and Attributes
 Entity


Entity class


person, place, thing, transaction, event
a ________, a collection of similar entities
Attributes

fields or columns in a table, characteristics of entities
 Keys and Relationships
 Primary key


A field or group of fields that uniquely identify an entity
_________ key

A primary key of one table that is a field of another table
Relational Database Advantages
 Increased Flexibility
 Physical view


_________ view


Physical storage of information on a device
How users logically access the information
Different users have different logical view to meet their needs
 Increased Scalability and Performance
 Scalability


How well a system can adapt to __________________
Performance

How quickly a system performs a process or transaction
Relational Database Advantages (2)
 Reduced Information Redundancy
 Redundancy

__________ duplication of information
 Increased Information Integrity (Quality)
 Information integrity


Measure of the quality of information
Integrity constraints
_________ to ensure the quality of information
 Relational integrity constraints ensure basic and fundamental quality
 Business-critical integrity constraints enforce business rules

 Increased Information Security (passwords, etc.)
Database Management Systems
 A database management system (DBMS) is software that
allows users to interact w/ a DB.
 A DBMS has several components

Data ____________ Component


Creates and maintains the data dictionary and DB structure
 Data dictionary stores definitions of information types
Data Manipulation Component
Allows users to do ________
 Create, read, update, and delete information
 A view allows users to see the contents of a DB
 Report generators are used to define reports from the DB
 QBE (________ by example) tools define answers to questions
 SQL (structured query language) is a language to query the DB

Database Management Systems (2)
 A DBMS has several components (continued)
 Application Generation Component


Contains tools for creating easy-to-use applications, such as SCM or
CRM
Data Administration Components

Contains tools for managing the overall database environment
 Backup, recovery, _________, and performance
Integrating Information among Multiple Databases
 An integration allows separate systems to communicate
directly with each other
 A __________integration takes new information and
sends it to all downstream systems and processes
 A backward integration takes processed information and
sends it automatically to all upstream systems and
processes
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