Detailed slides of data resource management. The relationships among the many individual data elements stored in databases are based on one of several logical data structures, or models.

1. DATA RESOURCE
MANAGEMENT
L E S S O N # 4

2. ORGANIZING DATA IN A TRADITIONAL
FILE ENVIRONMENT

3. FILE ORGANIZATION TERMS AND
CONCEPTS
Bit:
A bit represents the smallest unit of data a computer can handle.
Byte:
A group of bits, called a byte, represents a single character, which can be a letter, a number, or
symbol.
Filed:
A grouping of characters into a word, a group of words, or a complete number (such as a person’s
or age) is called a field.
Record:
A group of related fields, such as the student’s name, the course taken, the date, and the grade,
comprises a record
File:
A group of records of the same type is called a file.

4. CONT..
Entity:
A record describes an entity. An entity is a person, place, thing, or event on which we store
and maintain information.
Attribute:
Each characteristic or quality describing a particular entity is called an attribute.
Database:
A database is an integrated collection of logically related data elements. A database
consolidates records previously stored in separate files into a common pool of data
that provides data for many applications. The data stored in a database are independent of
the application programs using them and of the type of storage devices on which they are
stored.

5. DATABASE STRUCTURES
The relationships among the many individual data elements stored in databases are
based on one of several logical data structures, or models. Database management
system (DBMS) packages are designed to use a specific data structure to provide end
users with quick, easy access to information stored in databases.
Five fundamental database structures are
 The hierarchical model
 Network model
 Relational model
 Object-oriented model
 Multidimensional model

6. HIERARCHICAL STRUCTURE
• Early mainframe DBMS packages used
the hierarchical structure, in which the
relationships between records form a
hierarchy or treelike structure. In the
traditional hierarchical model, all
records are dependent and arranged
in multilevel structures, consisting of
one root record and any number of
subordinate levels.

7. NETWORK STRUCTURE
• The network structure can represent
more complex logical relationships
and is still used by some mainframe
DBMS packages. It allows many-to-
many relationships among records;
that is, the network model can access a
data element by following one of
several paths because any data
element or record can be related to
any number of other data elements.

8. RELATIONAL STRUCTURE
• The relational model is the most widely used of the three database structures. It is
used by most microcomputer DBMS packages, as well as by most midrange and
mainframe systems. In the relational model, all data elements within the database
are viewed as being stored in the form of simple two-dimensional tables,
sometimes referred to as relations . The tables in a relational database are flat files
that have rows and columns. Each row represents a single record in the file, and
each column represents a field.

9. MULTIDIMENSIONAL STRUCTURE
• The multidimensional model is a
variation of the relational model that
uses multidimensional structures to
organize data and express the
relationships between data. You can
visualize multidimensional structures
as cubes of data and cubes within
cubes of data. Each side of the cube is
considered a dimension of the data.

10. OBJECT-ORIENTED STRUCTURE
• The object-oriented model is considered
one of the key technologies of a new
generation of multimedia Web-based
applications. An object consists of data
values describing the attributes of an
entity, plus the operations that can be
performed upon the data. This
encapsulation capability allows the
object-oriented model to handle
complex types of data (graphics,
pictures, voice, and text) more easily
than other database structures.

11. DATABASE DEVELOPMENT
• Large organizations usually place control of enterprise wide database development in
the hands of database administrators (DBAs) and other database specialists. This
delegation improves the integrity and security of organizational databases. Database
developers use the data definition language (DDL) in database management systems
like Oracle 11g or IBM’s DB2 to develop and specify the data contents, relationships,
and structure of each database, as well as to modify these database specifications
when necessary. Such information is cataloged and stored in a database of data
definitions and specifications called a data dictionary, or metadata repository, which
is managed by the database management software and maintained by the DBA.

12. CONT..
• Data dictionary
A data dictionary is a database management catalog or directory containing metadata
(i.e., data about data). A data dictionary relies on a specialized database software
component to manage a database of data definitions.
• Metadata
Metadata is data that describes other data. Meta is a prefix that -- in most information
technology usages -- means "an underlying definition or description." Metadata
summarizes basic information about data, which can make finding and working with
particular instances of data easier.

13. DATA PLANNING AND DATABASE
DESIGN
• Database development may start with a top-down data planning process. Database
administrators and designers work with corporate and end-user management to
develop an enterprise model that defines the basic business process of the enterprise.
They then define the information needs of end users in a business process, such as the
purchasing/receiving process that all businesses have.

15. TYPES OF DATABASES

16. OPERATIONAL DATABASES
• Operational databases store detailed data needed to support the business processes
and operations of a company. They are also called subject area databases (SADB),
transaction databases, and production databases. Examples are a customer
human resource database, inventory database, and other databases containing data
generated by business operations.

17. DISTRIBUTED DATABASES
• Many organizations replicate and distribute copies or parts of databases to network
servers at a variety of sites. These distributed databases can reside on network servers
on the World Wide Web, on corporate intranets or extranets, or on other company
networks. Distributed databases may be copies of operational or analytical databases,
hypermedia or discussion databases, or any other type of database. Distributed
databases have both advantages and disadvantages.

18. EXTERNAL DATABASES
• Access to a wealth of information from external databases is available for a fee from
commercial online services and with or without charge from many sources on the World
Wide Web. Web sites provide an endless variety of hyperlinked pages of multimedia
documents in hypermedia databases for you to access.
• Data are available in the form of statistics on economic and demographic activity from
statistical databanks, or you can view or download abstracts or complete copies of
hundreds of newspapers, magazines, newsletters, research papers, and other published
material and periodicals from bibliographic and full-text databases.
• Whenever you use a search engine like Google or Yahoo to look up something on the
Internet, you are using an external database—a very, very large one! Also, if you are using
Google, you are using one that averages 112 million searches per day.

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20. DATA WAREHOUSES
• A data warehouse stores data that have been extracted from the various operational,
external, and other databases of an organization. It is a central source of the data that
have been cleaned, transformed, and cataloged so that they can be used by managers
and other business professionals for data mining, online analytical processing, and
other forms of business analysis, market research, and decision support.
• Data warehouses may be subdivided into data marts, which hold subsets of data from
the warehouse that focus on specific aspects of a company, such as a department or a
business process.

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23. DATA MINING
• Data mining is a major use of data warehouse databases and the static data they
contain. In data mining, the data in a data warehouse are analyzed to reveal hidden
patterns and trends in historical business activity. This analysis can be used to help
managers make decisions about strategic changes in business operations to gain
competitive advantages in the marketplace.
• Data mining can discover new correlations, patterns, and trends in vast amounts of
business data (frequently several terabytes of data) stored in data warehouses. Data
mining software uses advanced pattern recognition algorithms, as well as a variety of
mathematical and statistical techniques, to sift through mountains of data to extract
previously unknown strategic business information.

24. CONT..
• For example, many companies use data mining to:
Perform market-basket analysis to identify new product bundles.
Find root causes of quality or manufacturing problems.
Prevent customer attrition and acquire new customers.
Cross-sell to existing customers.
Profile customers with more accuracy.

25. CONT..

26. FILE PROCESSING SYSTEM
• A file processing system is a collection of programs that store and manage files in
computer hard-disk.
• On the other hand, A database management system is collection of programs that
enables to create and maintain a database.
• An organization relies on file processing systems in which data are organized, stored,
and processed in independent files of data records.

27. PROBLEMS OF FILE PROCESSING
• Data Redundancy. Independent data files included a lot of duplicated data; the same
data (such as a customer’s name and address) were recorded and stored in several
files.
• Lack of Data Integration. Having data in independent files made it difficult to provide
end users with information for ad hoc requests that required accessing data stored in
several different files. Special computer programs had to be written to retrieve data
from each independent file.
• Data Dependence. In file processing systems, major components of a system—the
organization of files, their physical locations on storage hardware, and the application
software used to access those files—depended on one another in significant ways.

28. CONT..
• Lack of Data Integrity or Standardization. In file processing systems, it was easy for
data elements such as stock numbers and customer addresses to be defined
by different end users and applications. This divergence caused serious inconsistency
problems in the development of programs to access such data. In addition, the
integrity (i.e., the accuracy and completeness) of the data was suspect because there
was no control over their use and maintenance by authorized end users. Thus, a lack
standards caused major problems in application program development and
maintenance, as well as in the security and integrity of the data files needed by the
organization.

29. THE DATABASE MANAGEMENT
APPROACH
• To solve the problems encountered with the file processing approach, the database
management approach was conceived as the foundation of modern methods for
managing organizational data. The database management approach consolidates data
records, formerly held in separate files, into databases that can be accessed by many
different application programs.
• In addition, a database management system (DBMS) serves as a software interface
between users and databases, which helps users easily access the data in a database.
Thus, database management involves the use of database management software to
control how databases are created, interrogated, and maintained to provide
information that end users need.

30. EXAMPLE
• For example, customer records and other common types of data are needed for
several different applications in banking, such as check processing, automated teller
systems, bank credit cards, savings accounts, and installment loan accounting. These
data can be consolidated into a common customer database, rather than being kept in
separate files for each of those applications.

31. DATABASE MANAGEMENT SYSTEM
• A database management system (DBMS) is the main software tool of the database
management approach because it controls the creation, maintenance, and use of the
databases of an organization and its end users.
• The database management system is an important system software package that
controls the development, use, and maintenance of the databases of computer-using
organizations.

33. DATABASE INTERROGATION
• A database interrogation capability is a major benefit of the database management
approach. End users can use a DBMS by asking for information from a database using
a query feature or a report generator.
• They can receive an immediate response in the form of video displays or printed
reports. No difficult programming is required.
• The report generator feature allows you to specify a report format for information you
want presented as a report.

34. CONT..

35. DATABASE MAINTENANCE
• The database maintenance process is accomplished by transaction processing systems
and other end-user applications, with the support of the DBMS. End users and
information specialists can also employ various utilities provided by a DBMS for
database maintenance. The databases of an organization need to be updated
continually to reflect new business transactions (e.g., sales made, products produced,
inventory shipped) and other events. Other miscellaneous changes also must be made
to update and correct data (e.g., customer or employee name and address changes) to
ensure the accuracy of the data in the databases.

36. APPLICATION DEVELOPMENT
• In addition, DBMS packages play a major role in application development. End users,
systems analysts, and other application developers can use the internal 4GL
programming language and built-in software development tools provided by many
DBMS packages to develop custom application programs. For example, you can use a
DBMS to develop the data entry screens, forms, reports, or Web pages of a business
application that accesses a company database to find and update the data it needs. A
DBMS also makes the job of application software developers easier, because they do
not have to develop detailed data-handling procedures using conventional
programming languages every time they write a program. Instead, they can include
features such as data manipulation language (DML) statements in their software that
call on the DBMS to perform necessary data-handling activities.

37. C O N T A C T I N F O .
H U M A S H E I K H 1 0 7 @ G M A I L . C O M