Chapter 1
User interface
( languages, menus, and other facilities by which users interact with the various system components)
Repository Vs Database
(a repository is a centralized storehouse for all data definitions, data relationships, and other system components, while a database is organized collection of logically related data.)
Five disadvantages of file processing system
(a. program-data dependence b. duplication of data c. limited data sharing d. lengthy development times e. excessive program maintenance)
Entity Vs Enterprise data model
(an entity is an object or concept that is important to the business, while an enterprise data model is a graphical model that shows the high-level entities for the organization and the relationship among those entities.)
Application programs
(computer programs that are used to create and maintain the database.)
Data Vs Information
(data consist of facts, text, and other multimedia objects, while information is data that have been processed in such a way that it can increase the knowledge of the person who use it.)
Data warehouse Vs Data mining
(data warehouse is an integrated decision support database, while data mining is the process of extracting useful information from databases.)
Database
(organized collection of logically related data.)
Data dependence Vs Data independence
(with data dependence, data descriptions are included with the application programs that use the data, while with data independence the data description are separated from the application programs.)
What is data independence and what are the important goals
Data independence refers to the separation of data descriptions from the application programs that use the data. It is an important goal because it allows an organization's data to change and evolve without changing the application programs that use the data.
Enterprise data model-
a graphical model that shows the high-level entities for the organization and the relationships among those entities.
Entity
a person, place, object, event, or concept in the user environment about which the organization wishes to maintain data.
Constraint
a rule that cannot be violated by database users
Database management system
a software application that is used to create, maintain and provide controlled access to user databases.
Five additional costs or risks of the database approach are
a) new, specialized personnel b) installation, management cost, and complexity c)conversion costs d) need for explicit backup and recovery e) organizational conflict
Potential benefits of the database approach are:
a)programs-data independence b) minimal data redundancy c) improved data consistency d) improved data sharing e) increased development productivity f) enforcement standards g) improved data quality h) improved data accessibility and responsiveness i) reduced program maintenance j) improved decision support
Database
an organized collection of logically related data
Database application
application programs
case tools:
automated tools used to design database applications.
Repository
centralized storehouse for all data definitions
Repository
centralized storehouse of data definitions
Database management system (DBMS)-
commercial software used to define, create, maintain, and provide controlled access to the database and the repository.
Information
data placed in context or summarized
Data
facts, text, graphics, images, etc.
Metadata
includes data definitions and constraints
Data warehouse
integrated decision support database
User view
logical description of portion of database
Database
organized collection of related data
System developers
person such as systems analysts and programmers who design new application programs.
End users
person who add, delete, and modify data in the database and who request information from it.
Data administrators
persons who are responsible for the overall information resources of an organization
Enterprise resource systems
planning a business management system that integrates all functions of the enterprise(ERP)
Data independence
separation of data description from programs
