This document discusses databases and database management. It begins by explaining the problems with traditional file-based data storage and how a database management system (DBMS) addresses these issues by centralizing data. The DBMS acts as an interface between applications and data storage. Key components of a DBMS include data definition and manipulation languages and a data dictionary. The document then covers database design, trends like data warehousing and online analytical processing, and how databases are used on the web.

1. MANAGING
DATA
RESOURCES

2. OBJECTIVES
 Why do businesses have trouble finding the
information they need in their information
systems?
 How does a DBMS improve the organization of
business information?
 What are the managerial requirements of a
data-base environment?
 What new technologies make databases more
accessible and useful?

3. ORGANIZING DATA IN A TRADITIONAL FILE
ENVIRONMENT
A computer system organizes data in a hierarchy that
starts with bits and progresses to field, records,
files, and databases
Bit: Smallest unit of data; binary digit (0,1)
Byte: Group of bits that represents a single character
(letter, a number or symbol)
Field: Group of related bytes ( complete word or a
complete number like name, age etc.,)
- related words or a complete number
Record: Group of related fields(such as student’s name,
course taken,section,grade etc.,)
File: Group of records of same type(students records
constitute a course file)
Database: Group of related files( course file, financial file,
personal history file)

4. ORGANIZING DATA IN A TRADITIONAL FILE
ENVIRONMENT
File Organization Terms and Concepts

5. ORGANIZING DATA IN A TRADITIONAL FILE
ENVIRONMENT
File Organization Terms and Concepts
 Entity: Person, place, thing, event about
which information is maintained(An order is
a typical entity in a sales order file)
 Attribute: Description of a particular entity
(characteristic or quality, order number,
order date, amount, item no., and item
quantity )
 Key Field: Unique identifier field used to
retrieve, update, or sort a record

6. ORGANIZING DATA IN A TRADITIONAL FILE
ENVIRONMENT
Problems with the Traditional File Environment
 Data redundancy
 Program-data dependence
 Lack of flexibility
 Poor security
 Lack of data-sharing and availability

7. ORGANIZING DATA IN A TRADITIONAL FILE
ENVIRONMENT
Problems with the Traditional File Environment

8.  Data Redundancy-It is the presence of duplicate data in
multiple data files.
 Program Data Independence – it is the tight relationship
between data stored in files and the specific programs
required to update and maintain those files.
 Lack of Flexibility-A traditional file system can deliver
routine scheduled reports after expensive programming
efforts, but it cannot deliver ad hoc reports to respond to
anticipated information requirements in a timely fashion.
 Poor security – Because there is little control of
management of data, access to and dissemination of
information may out of control
 Lack of data sharing and availability –It is not easy to
obtain information because pieces of information in
different files and different parts of the organisation
cannot be related to one another, it is virtually impossible
information to be shared or accessed in a timely manner.

9. ORGANIZING DATA IN A TRADITIONAL FILE
ENVIRONMENT
File Organization Terms and Concepts
Order number is the key field because each order is
assigned a unique identification number

10. THE DATABASE APPROACH TO DATA MANAGEMENT
Database Management System (DBMS)
Database
• A collection of data organized to service many applications at
the same time by storing and managing data so they appear
to be at one location
• A collection of data organized to service many applications
efficiently by centralising the data and minimising redundant
data.
• A single data base service multiple applications
• Ex: Instead of a Corporation storing employee data in
separate information systems and separate files for
personnel, payroll and benefits , the Corpotation could create
a single common human resources database

11. THE DATABASE APPROACH TO DATA MANAGEMENT
A single HRDB serves multiple applications and also
allows a corporation to easily draw together all
the Information for various applications. The DBMS
acts as the interface between the application programs

12. THE DATABASE APPROACH TO DATA MANAGEMENT
Database Management System (DBMS)
Database technology can cut through many of the problems a
traditional file organization creates
DBMS is a special software to create and
maintain a database and enable
individual business applications to
extract the data they need without
having to create separate files or data
definitions in their computer programs.

13. THE DATABASE APPROACH TO DATA MANAGEMENT
Database Management System (DBMS)
Database technology can cut through many of the problems a
traditional file organization creates
The Database Management System (DBMS) is simply a software
• which creates and maintains databases
• that permits an organisation to cdntralise data, manage them
efficiently and provide access to the stored data by
application programs.
• Eliminates most of the data definition statements found in
traditional programs
• Acts as interface between application programs and physical
data files
• Separates logical and physical views of data

14. THE DATABASE APPROACH TO DATA MANAGEMENT
Database Management System (DBMS)
Database technology can cut through many of the problems a
traditional file organization creates
The logical view presents data as they would be percieved by end
users or business specialists whereas
Physical view shows how data are actually organised and
structured on physical storage media
There is only one physical view of the data but different logical
views. The DBMS software makes the physical database
available for different logical views presented for various
application programs
An employee retirement benefits program might use a logical
view of the human resources data base that requires only the
employees name, address, social security number, pension
plan, and retirement benefits data.

15. 7.2 THE DATABASE APPROACH TO DATA MANAGEMENT
Database Management System (DBMS)
Components of a Database
• Data Definition Language:
– Specifies content and structure of
database and defines each data element
• Data Manipulation Language:
– Manipulates data in a database
• Data Dictionary:
– Stores definitions of data elements, and
data characteristics

16. THE DATABASE APPROACH TO DATA
MANAGEMENT
Types of Databases
• Hierarchical DBMS
• Organizes data in a tree-like structure
• Prevalent in large legacy systems
• Less flexible than RDBMS
• Lacks support for English language-like queries
• Relational DBMS (RDBMS)
• Represents data as 2D tables called ‘relations’
• Relates data across tables based on ‘key’
• Egs: DB2, Oracle, MS SQL Server, MS Access

17. THE DATABASE APPROACH TO DATA
MANAGEMENT
Types of Databases

18. THE DATABASE APPROACH TO DATA
MANAGEMENT
Types of Databases

19. THE DATABASE APPROACH TO DATA
MANAGEMENT
Types of Databases
Three Basic Operations in a Relational
DBMS
• Select: Creates subset of rows that meet
specific criteria
• Join: Combines relational tables to provide
users with information
• Project: Enables users to create new tables
containing only relevant information

20. THE DATABASE APPROACH TO DATA MANAGEMENT
Types of Databases

21. CREATING A DATABASE ENVIRONMENT
Designing Databases
 Entity-Relationship (ER) Diagram
◦ Methodology for documenting databases
illustrating relationships between database
entities
 Normalization
◦ Process of creating small stable data structures
from complex groups of data

22. CREATING A DATABASE ENVIRONMENT
Designing Databases

23. CREATING A DATABASE ENVIRONMENT
Designing Databases

24. 7.3 CREATING A DATABASE ENVIRONMENT
Designing Databases

25. 7.4 DATABASE TRENDS
Multidimensional Data Analysis
On-line Analytical Processing (OLAP)
 Multidimensional data analysis
 Supports manipulation and analysis of
large volumes of data from multiple
dimensions/perspectives

26. 7.4 DATABASE TRENDS
Multidimensional Data Analysis

27. 7.4 DATABASE TRENDS
Data Warehouses and Datamining
Data Warehouse
 Consolidates current and historical data
 Supports query tools for management
decision making
Datamining
 Tools for finding hidden patterns and
relationships in large pools of data

28. 7.4 DATABASE TRENDS
Data Warehouses and Datamining

29. 7.4 DATABASE TRENDS
Data Warehousing and Datamining

30. 7.4 DATABASE TRENDS
Databases and the Web
The Web and Hypermedia Databases
• Organizes data as network of hyperlinks
• Database Server runs a DBMS to provide
data
• Supports text, graphics, sound, video
and executable programs

31. 7.4 DATABASE TRENDS
Databases and the Web

32. 7.4 DATABASE TRENDS
Databases and the Web

33. 7.4 DATABASE TRENDS
Databases and the Web

34. 7.4 DATABASE TRENDS
Databases and the Web

35.  A database administrator (short form DBA) is a person responsible for
the design, implementation, maintenance and repair of an organization's
database. They are also known by the titles Database Coordinator or
Database Programmer, and is closely related to the Database Analyst,
Database Modeller, Programmer Analyst, and Systems Manager.
 The role includes the development and design of database strategies,
monitoring and improving database performance and capacity, and
planning for future expansion requirements. They may also plan, co-
ordinate and implement security measures to safeguard the database.
 Employing organizations may require that a database administrator have
a certification or degree for database systems (for example, the
Microsoft Certified Database Administrator. Some organizations have a
hierarchical level of database administrators, generally:
 Data Analysts/Query designers
 Junior DBAs
 Midlevel DBAs
 Senior DBAs
 DBA consultants
 Manager/Director of Database Administration/Information Technology

36. SKILLS:
 Strong organizational skills
 Strong logical and analytical thinker
 Ability to concentrate and pay close attention to
detail
 Ability to think broadly and consider impacts across
systems and within the organization
DUTIES:
 Transferring Data
 Replicating Data
 Maintaining database and ensuring its availability to
users
 Maintaining the data dictionary
 Controlling privileges and permissions to database
users
 Monitoring database performance
 Database backup and recovery
 Database security Stop

37.  The Database Analyst's role is to direct, evaluate,
review, and manage database resources and
services across the organization while ensuring
high levels of data quality. This individual is also
responsible for developing, implementing, and
overseeing database policies and procedures to
ensure the integrity and availability of databases
and their accompanying software. Where
required, the Database Analyst will design,
install, monitor, maintain, and performance tune
production databases.

38.  Database design is the process of producing a detailed data model of a database. This logical
data model contains all the needed logical and physical design choices and physical storage
parameters needed to generate a design in a Data Definition Language, which can then be used
to create a database. A fully attributed data model contains detailed attributes for each entity.
 The term database design can be used to describe many different parts of the design of an
overall database system. Principally, and most correctly, it can be thought of as the logical
design of the base data structures used to store the data. In the relational model these are the
tables and views. In an object database the entities and relationships map directly to object
classes and named relationships. However, the term database design could also be used to
apply to the overall process of designing, not just the base data structures, but also the forms
and queries used as part of the overall database application within the database management
system (DBMS).[
 In a majority of cases, a person who is doing the design of a database is a person with
expertise in the area of database design, rather than expertise in the domain from which the
data to be stored is drawn e.g. financial information, biological information etc. Therefore the
data to be stored in the database must be determined in cooperation with a person who does
have expertise in that domain, and who is aware of what data must be stored within the
system.
 This process is one which is generally considered part of requirements analysis, and requires
skill on the part of the database designer to elicit the needed information from those with the
domain knowledge. This is because those with the necessary domain knowledge frequently
cannot express clearly what their system requirements for the database are as they are
unaccustomed to thinking in terms of the discrete data elements which must be stored. Data to
be stored can be determined by Requirement Specification.[