ICT3621
NOTES
,Chapter 1: Database Approach
Data are raw facts.
Information is the result of processing raw data to reveal its meaning
Data management is a discipline that focuses on the proper generation, storage, and
retrieval of data.
A database is a shared, integrated computer structure that stores a collection of: _
End-user data, that is, raw facts of interest to the end user.
Metadata, or data about data, through which the end-user data are integrated and
managed.
A database management system (DBMS) is a collection of programs that manages
the database structure and controls access to the data stored in the database.
DBMS provides advantages such as:
Improved data sharing. The DBMS helps create an environment in which end users
have better access to more and better-managed data. Such access makes it possible for
end users to respond quickly to changes in their environment.
Improved data security. The more users access the data, the greater the risks of data
security breaches.
Better data integration. Wider access to well-managed data promotes an integrated
view of the organization’s operations and a clearer view of the big picture.
Minimized data inconsistency. Data inconsistency exists when different versions of
the same data appear in different places.
Improved data access. The DBMS makes it possible to produce quick answers to ad
hoc queries. From a database perspective, a query is a specific request issued to the
DBMS for data manipulation.
Improved decision making. Better-managed data and improved data access make it
possible to generate better-quality information, on which better decisions are based.
Increased end-user productivity. The availability of data, combined with the tools that
transform data into usable information, empowers end users to make quick, informed
decisions that can make the difference between success and failure in the global
economy
Data quality is a comprehensive approach to promoting the accuracy, validity, and
timeliness of the data
, Types of Databases
A single-user database supports only one user at a time.
A single-user database that runs on a personal computer is called a desktop database.
A multiuser database supports multiple users at the same time.
A workgroup database is when the multiuser database supports a relatively small
number of users (usually fewer than 50)
An enterprise database is when the database is used by the entire organization and
supports many users (more than 50, usually hundreds)
A database that supports data located at a single site is called a centralized database.
A database that supports data distributed across several different sites is called a
distributed database.
A database that is designed primarily to support a company’s day-to-day operations is
classified as an operational database (sometimes referred to as a transactional or
production database).
A data warehouse focuses primarily on storing data used to generate information
required to make tactical or strategic decisions.
Unstructured data are data that exist in their original (raw) state, that is, in the
format in which they were collected.
Structured data are the result of taking unstructured data and formatting
(structuring) such data to facilitate storage, use, and the generation of information.
Semistructured data are data that have already been processed to some extent.
Extensible Markup Language (XML) is a special language used to represent and
manipulate data elements in a textual format.
An XML database supports the storage and management of semistructured XML
data.
Database design refers to the activities that focus on the design of the database
structure that will be used to store and manage end-user data.
A data processing (DP) specialist was hired to create a computer-based system that would
track data and produce required reports.
TERM DEFINITION
Field A character or group of characters (alphabetic or numeric) that has a specific
meaning.
Record A logically connected set of one or more fields that describes a person, place,
or thing.
File A collection of related records. For example, a file might contain data about the
students currently enrolled at Unisa.
The following problems associated with file systems, whether created by DP specialists or
through a series of spreadsheets, severely challenge the types of information that can be
created from the data as well as the accuracy of the information:
Lengthy development times.
NOTES
,Chapter 1: Database Approach
Data are raw facts.
Information is the result of processing raw data to reveal its meaning
Data management is a discipline that focuses on the proper generation, storage, and
retrieval of data.
A database is a shared, integrated computer structure that stores a collection of: _
End-user data, that is, raw facts of interest to the end user.
Metadata, or data about data, through which the end-user data are integrated and
managed.
A database management system (DBMS) is a collection of programs that manages
the database structure and controls access to the data stored in the database.
DBMS provides advantages such as:
Improved data sharing. The DBMS helps create an environment in which end users
have better access to more and better-managed data. Such access makes it possible for
end users to respond quickly to changes in their environment.
Improved data security. The more users access the data, the greater the risks of data
security breaches.
Better data integration. Wider access to well-managed data promotes an integrated
view of the organization’s operations and a clearer view of the big picture.
Minimized data inconsistency. Data inconsistency exists when different versions of
the same data appear in different places.
Improved data access. The DBMS makes it possible to produce quick answers to ad
hoc queries. From a database perspective, a query is a specific request issued to the
DBMS for data manipulation.
Improved decision making. Better-managed data and improved data access make it
possible to generate better-quality information, on which better decisions are based.
Increased end-user productivity. The availability of data, combined with the tools that
transform data into usable information, empowers end users to make quick, informed
decisions that can make the difference between success and failure in the global
economy
Data quality is a comprehensive approach to promoting the accuracy, validity, and
timeliness of the data
, Types of Databases
A single-user database supports only one user at a time.
A single-user database that runs on a personal computer is called a desktop database.
A multiuser database supports multiple users at the same time.
A workgroup database is when the multiuser database supports a relatively small
number of users (usually fewer than 50)
An enterprise database is when the database is used by the entire organization and
supports many users (more than 50, usually hundreds)
A database that supports data located at a single site is called a centralized database.
A database that supports data distributed across several different sites is called a
distributed database.
A database that is designed primarily to support a company’s day-to-day operations is
classified as an operational database (sometimes referred to as a transactional or
production database).
A data warehouse focuses primarily on storing data used to generate information
required to make tactical or strategic decisions.
Unstructured data are data that exist in their original (raw) state, that is, in the
format in which they were collected.
Structured data are the result of taking unstructured data and formatting
(structuring) such data to facilitate storage, use, and the generation of information.
Semistructured data are data that have already been processed to some extent.
Extensible Markup Language (XML) is a special language used to represent and
manipulate data elements in a textual format.
An XML database supports the storage and management of semistructured XML
data.
Database design refers to the activities that focus on the design of the database
structure that will be used to store and manage end-user data.
A data processing (DP) specialist was hired to create a computer-based system that would
track data and produce required reports.
TERM DEFINITION
Field A character or group of characters (alphabetic or numeric) that has a specific
meaning.
Record A logically connected set of one or more fields that describes a person, place,
or thing.
File A collection of related records. For example, a file might contain data about the
students currently enrolled at Unisa.
The following problems associated with file systems, whether created by DP specialists or
through a series of spreadsheets, severely challenge the types of information that can be
created from the data as well as the accuracy of the information:
Lengthy development times.
