Section I: Managing Data Resources
DATA
RESOURCE MANAGEMENT
Data is a
vital organizational resource, which needs to be managed like other important
business assets. Most organizations
could not survive or succeed without quality data about their internal
operations and external environment.
Managers need to practice data resource management - a
managerial activity that applies information systems technology like database
management and other management tools to the task of managing an
organization's data resources to meet the information needs of business users.
FOUNDATION
DATA CONCEPTS
A
hierarchy of several levels of data has been devised that differentiates
between different groupings, or elements, of data. Data are logically organized into:
·
Character - A character is the most basic logical
data element. It consists of a single
alphabetic, numeric, or other symbol.
·
Field - A field consists of a grouping of
characters. A data field represents an attribute
(a characteristic or quality) of some entity (object, person,
place, or event).
·
Record - Related fields of data are grouped to form a record. Thus, a record represents a
collection of attributes that describe an entity. Fixed-length records contain a fixed
number of fixed-length data fields. Variable-length
records contain a variable number of fields and field lengths.
·
File - A group of related records is known as a data file,
or table. Files are frequently
classified by the application for which they are primarily used, such as a payroll
file or an inventory file, or the type of data they contain, such as
a document file or a graphical image file. Files are also classified by their
permanence, for example, a master file versus a transaction
file. A transaction file would
contain records of all transactions occurring during a period, whereas a master
file contains all the permanent records.
A history file is an obsolete transaction or master file retained
for backup purposes or for long-term historical storage called archival
storage.
·
Database - A database is an integrated collection of logically
related records or objects. A database
consolidates records previously stored in separate files into a common pool of
data records that provides data for many applications. The data stored in a database is independent
of the application programs using it and of the type of secondary storage
devices on which it is stored.
TYPES OF
DATABASES
Continuing
developments in information technology and its business applications have
resulted in the evolution of several major types of databases. Several major
conceptual categories of databases that may be found in computer-using
organizations include:
·
Operational Databases - These
databases store detailed data needed to support the operations of the entire
organization. They are also called subject
area databases (SADB), transaction databases, and production
databases. Examples are customer
databases, personnel databases, inventory databases, and other databases
containing data generated by business operations.
·
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. Replication and
distribution of databases is done to improve database performance and security.
·
External Databases - Access to
external, privately owned online databases or data banks is available for a fee
to end users and organizations from commercial online services, and with or
without charge from many sources on the Internet, especially the Web.
·
Hypermedia Databases on the Web: [Figure
3.6] - The rapid growth of web sites on the
Internet and corporate Intranets and extranets has dramatically increased the
use of databases of hypertext and hypermedia documents. A web site stores such
information in a hypermedia database consisting of a home page and other
hyperlinked pages of multimedia or mixed media (text, sound, etc.).
DATA
WAREHOUSES AND DATA MINING
·
Data Warehouses - A data
warehouse stores data from current and previous years that has been extracted
from the various operational and management databases of an organization. It becomes a central source of data, which
has been screened, edited, standardized, and integrated so it can be used by
managers and other end user professionals throughout an organization. Data warehouses may be subdivided into data
marts, which hold specific subsets of data from the warehouse.
·
Data Mining - A major use of data
warehouse databases is data mining. In data mining, the data in a data warehouse
are processed to identify key factors and trends in historical patterns of
business activity that can be used to help managers make decisions about
strategic changes in business operations to gain competitive advantages in the
marketplace.



