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CID 2003
Database
Management
Systems
LO1: Discuss the importance
of database control
measures including data
security, backup and data
recovery.
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Topics
 Data,
Databases, and (DBMS)
Database Management System
 Security
Issues
 Backup
and Recovery
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What is Data?
A
single piece of data is a single fact about
something that interests us.
A
fact can be any characteristic of an object .
Salesperson Salesperson
Number
Name
137
Baker
Cit y
Detroit
State
MI
Figur e 2.1 Facts about salesperson Baker.
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Office
Number
1284
Commi ssion Year of
Percentage
Hir e
10
1995
What is Data ?
Examples:
Collecting facts about mobiles

This is Data
Collecting facts about students

This is Data
Collecting facts about cars

This is Data
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Database &
Database Management
System (DBMS)
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What is a Database?
• It’s an organized collection of data.
What is a Database Management System (DBMS)?
•
A database management system (DBMS) is
the software you need to organize that data
in a flexible manner.
•
This software includes tools to add, modify or
delete data from the database, ask
questions (or queries) about the data stored
in the database and produce reports
summarizing selected contents.
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 DBMS
provides an interface between
the user and the data”
 Examples
of Relational Database
Management Systems:
 Oracle
(from Oracle Corporation)
 SQL Server (from Microsoft)
 MS Access (small-from Microsoft)
 DB2 (from IBM)
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Database Management Systems DBMS
Oracle
Rules That Manage
the Database
Users
DBMS
software
HCT
Database
Data stored in
computer files
on Disk.
Database
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The Database Environment






Encourages data sharing
Helps control data redundancy (Less duplicate
data entry )
ensures data accuracy
Permits storage of vast volumes of data with
acceptable access speed.
Allows database queries (Easier and faster to
find data)
Provides tools to control:



data security
data privacy
backup and recovery
The coming
slides will explain
these concepts
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Data Privacy



Every organization or individual has to limit
what data can be shared with third parties.
e.g. making sure that even employees who
normally have access to the company’s data
are given access only to the specific data
that they need in their work.
e.g. patient confidentiality for all healthcarerelated data.
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Data Security
 Every
company must
protect its data from theft, malicious
(nasty)destruction, deliberate attempts to
change the data.
 e.g.
someone trying to
increase his/her own bank
account balance.
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Methods of Breaching Data Security
(to illegally access data )
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Methods of Breaching Data Security
 Unauthorized
 Intercepting
 Stealing
Computer Access
Data Communications
Disks or Computers
 Computer
Viruses
 Damaging
Computer Hardware
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Backup and Recovery
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Backup and Recovery
The ability to reconstruct data if it is lost or
corrupted.

e.g., following a hardware failure

e.g., following a natural disaster
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Backup and Recovery
 We
have to assume that from time to time
something will go wrong with our data, and so we
have to have the tools available to correct or
reconstruct it.
 Data
backups
•
are one of the most effective ways of protecting
against data loss.
•
Establish data backup procedures (ways of doing
something) e.g. Backup Daily, Weekly etc
•
Storage for data backups, and securing data backups
using passwords.
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Backup
 On
a regularly scheduled
basis, a company’s databases
must be backed up or copied.
(daily/weekly/monthly…etc)
 The
backup copy must be
put in a safe place, away
from the original in the
computer system.
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Data Recovery
 Data
recovery is the process of
recovering or reconstructing data from
the backup copy when it cannot be
accessed normally( maybe it got
corrupted or lost)
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