Chapter 10
Database
Management
“If you want to leave footprints in the
sands of time, don’t drag your feet.”
Data vs. Information
Data - raw facts
Information - processed data


Data integrity- accuracy of data
Data security - protecting data
Data and Information
What is data integrity?

Degree to which data is
correct

Garbage in, garbage
out (GIGO)—computer
phrase that means you
cannot create correct
information from
incorrect data
Garbage in
Garbage out
Data integrity
is lost
p. 10.03
Next
Data and Information
What is a database?
Collection of data
organized so
you can access,
retrieve, and
use it
Database software
allows you to
Create
database
Click to view animation
p. 10.03
Database software
also called database
management system
(DBMS)
Add,
change,
and delete
data
Sort
and
retrieve
data
Create
forms
and
reports
Next
Data and Information
What are the qualities of valuable information?
Accurate
Verifiable
Timely
Organized
Accessible
Useful
Cost-effective
p. 10.04
Next
Hierarchy of Data
Bit - one binary digit
Byte - eight bits
Field - one or more characters (name, ssno)
Record - collection of related fields
File - collection of related records
Database - collection of related files
The Hierarchy of Data
records
p. 10.07
Member ID
First Name
Last Name
Address
City
State
2295
Donna
Vandenberg
1029 Wolf Avenue
Montgomery
AL
2928
Shannon
Murray
33099 Clark Street
Montgomery
AL
3376
Adrian
Valesquez
15 Duluth Street
Prattville
AL
3928
Jonah
Weinberg
P.O. Box 45
Clanton
AL
4872
Marcus
Green
22 Fifth Avenue
Auburn
AL
key
field
fields
Next
Maintaining Data
What is file maintenance?

Procedures that keep data current
Adding records
Changing records
Deleting records
p. 10.08
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Maintaining Data
What is validation?


Process of
comparing data
with a set of rules
to find out if data
is correct
Reduce data entry
errors and
enhance data
integrity before
program writes
data on disk
p. 10.10 Fig. 10-8
SAMPLE VALID AND INVALID DATA
Validity
Check
Field Being
Checked
Valid Data Invalid Data
Alphabetic
Check
First Name
Adrian
Ad33n
Numeric
Check
Postal Code
36109
3rto9
Range Check
Monthly Fee $39.50
Consistency
Check
Date Joined
Training
Date
Last Name
Completeness
Check
$95.25
10-20-2004 10-20-2004
10-27-2004 10-13-2004
Valesquez
Next
File processing vs. databases
File processing system (flat files)


data redundancy
isolated data
File Processing Versus Databases
What is the database approach?


Many programs and users can share data in database
Secures data so only authorized users can access
certain data
p. 10.12 Fig. 10-9
Next
File Processing Versus Databases
What are the strengths of the database approach?
Reduced
data
redundancy
Improved
data
integrity
Shared
data
Easier
access
p. 10.13
Reduced
development
time
Next
Database Management Systems
What are popular database management systems (DBMSs)?
Click to view Web Link,
then click Database
Management System
below Chapter 10
p. 10.14
Database
Manufacturer
Computer Type
Access
Microsoft Corporation
Personal computer, server, PDA
DB2
IBM Corporation
Personal computer, midrange
server, mainframe
Informix
IBM Corporation
Personal computer, midrange
server, mainframe
Ingres
Computer Associates
International, Inc.
Personal computer, midrange
server, mainframe
Oracle
Oracle Corporation
SQL Server
Microsoft Corporation
Personal computer, midrange
server, mainframe, PDA
Server
Sybase
Sybase Inc.
Personal computer, midrange
server, PDA
Next
DBMS
Data Base Management System (DBMS)

set of programs designed to control access to the
database and manage the data




Data dictionary
Data maintenance and retrieval - query language
Data security
Backup and recovery
Database Management Systems
What is a data dictionary?

Contains data about each file in database and each
field within those files
Click to view Web Link,
then click Data Dictionary
below Chapter 10
p. 10.14 Fig. 10-12
Next
Database Management Systems
Step 1. Select the fields you want
What is a query?


Request for specific data from
a database
Query language consists of
simple, English-like statements
that allow users to specify data
to display, print, or store
to display in the resulting query.
Step 2. Assign a name to the
query, so you can open it later.
Step 3. View query on the screen.
p. 10.16 Fig. 10-13
Next
Database Management Systems
What is data security?
Access
privileges
define activities
that specific user
or group of users
can perform
DBMS provides
means to ensure
only authorized
users can access
data
Read-only
privileges
user can
view data,
but cannot
change it
p. 10.18
Full-update
privileges
user can
view and
change data
Next
Types of Databases
Relational database - links files through the use of a
common field
Object-oriented database - database based on an
object-oriented model. Can store more types of
data and access it faster (photos, video clips)
Databases cont.
Hierarchial database - (tree structure) - organized like
a family tree - each parent can have more than one
child, but each child may have only one parent
Network database - Like an hierarchial database
except that each child may have more than one
parent
Multidimensional Database – Stores data in
dimensions (can store more than two dimensions –
ex. Storing text and video clips)
Relational, Object-Oriented, and Multidimensional Databases
What is a relational database?

Stores data in tables that consist of rows and columns




Each row has primary key
Each column has unique name
Stores data relationships
Uses specialized terminology
DATA TERMINOLOGY
Click to view Web Link,
then click Relational
Databases below Chapter 10
p. 10.20 Fig. 10-19
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Relational, Object-Oriented, and Multidimensional Databases
What is a relationship?

Connection
within data
Click to view animation
p. 10.21 Fig. 10-20
Next
Relational, Object-Oriented, and Multidimensional Databases
What is an object-oriented database (OODB)?
Stores data in objects
Advantages
Object is item that contains data,
as well as actions that read or
process data
 Can store more types of data
 Can access data faster
Often uses object query language (OQL)
Click to view Web Link,
then click Object-Oriented
Databases below Chapter 10
p. 10.22
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Relational, Object-Oriented, and Multidimensional Databases
What is a multidimensional database?
Stores data in
dimensions
Multiple dimensions, also
called hypercube, allow users
to analyze any view of data
Can consolidate data much
faster than relational database
Click to view Web Link,
then click Multidimensional
Databases below Chapter 10
p. 10.23
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Web Databases
What is a Web database?


Database you access through the Web by filling in a form
on a Web page
Usually resides on
a database server, a
computer that
stores and provides
access to a
database
Click to view video
p. 10.24 Fig. 10-23
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Database Administration
What is the role of the database analyst and
administrator?
Database analyst (DA)
 Focuses on meaning and
usage of data
 Decides proper placement
of fields, defines
relationships, and
identifies users’ access
privileges
Database administrator
(DBA)
 Creates and maintains data
dictionary, manages
database security,
monitors database
performance, and checks
backup and recovery
procedures
Click to view Web Link,
then click Database
Administrators
below Chapter 10
p. 10.27
Next
That’s all folks