1. Database Systems
Chapter 3 1

2. Data Management
Without data and the ability to process the data an organization could not successfully complete most business activities (e.g., pay employees, order new inventory)
Data consists of raw facts
To transform data into useful information it must first be organized in a meaningful way

3. Logical Data Elements Data may be logically organized into: character
field
record
file
database

4. Logical Data Elements Character Field (data item) Record
File (table, flat file)
Database
A basic building block of most information, consisting of:
uppercase letters,
lowercase
Letters
numeric digits
special symbols
Example:
A,B,c
0,1,8
_,%,&
Typically a name, number, or combination of characters that describes an aspect of a business object or activity.
Examples:
salary, job title
A collection of data fields all related to one object, activity, or individual.
Example:
payroll records with name, SSN, pay rate
A collection of related records.
Example: employee file
a collection of integrated and related files.

6. Why Learn About Database Systems, Data Centers, and Business Intelligence?
Organized collection of data
Database management system (DBMS):
Group of programs that manipulate the database
Provide an interface between the database
and its users and other application programs
Database administrator (DBA):
Skilled IS professional who directs all activities
related to an organization’s database

7. Data Entities, Attributes, and Keys
Entities, attributes, and keys are important database concepts.
Entity:
General class of people, places, or things (objects) for which data is collected, stored, and maintained
EX: employee, customer and inventory.
Attribute:
Characteristic of an entity
EX: employee number, first name, hire date
Data item:
Specific value of an attribute

8. Data Entities, Attributes, and Keys

9. Data Entities, Attributes, and Keys
Field or set of fields in a record that is used to identify the record
Primary key:
Field or set of fields that uniquely identifies the record.
The primary key is used to distinguish records so that they can be accessed, organized, and manipulated.
Primary keys ensure that each record in a file is unique.
Ex. Employee#, Student_ID

10. The Database Approach Traditional approach to data management:
An approach to data management whereby each distinct operational system used data files dedicated to that system.
Database approach to data management:
An approach to data management whereby a pool of related data is shared by multiple information systems.
To use the database approach to data management, additional software is required
a database management system (DBMS)

11. The Database Approach (continued)

12. Advantages of the Database Approach

13. Disadvantages of the Database Approach