MIS 331 Exam 1
Which of the following is data redundancy? (a) same data field shows in more than one data file (b) same data file has more than one copy (c) any changes in the data file structure will prevent user from accessing the data (d) metadata are stored within each application program that accesses the data
(a) same data field shows in more than one data file
Which of the following is data duplication? (a) same data field shows in more than one data file (b) same data file has more than one copy (c) any changes in the data file structure will prevent user from accessing the data (d) metadata are stored within each application program that accesses the data
(b) same data file has more than one copy
Which of the following is program-data dependence? (a) same data field shows in more than one data file (b) same data file has more than one copy (c) any changes in the data file structure will prevent user from accessing the data (d) metadata are stored within each application program that accesses the data
(d) metadata are stored within each application program that accesses the data
Repository
A centralized knowledge base of all data definitions, data relationships, screen and report formats, and other system components.
relational database
A database that represents data as a collection of tables in which all data relationships are represented by common values in related tables
Conceptual Schema
A detailed, technology-independent specification of the overall structure of organizational data (Analysis)
Installation and Management Cost and Complexity (Costs and Risks of the Database Approach)
A multiuser database management system is a large and complex suite of software that has a high initial cost, requires a staff of trained personnel to install and operate, and has substantial annual maintenance and support costs
project
A planned undertaking of related activities to reach an objective that has a beginning and an end.
Constraint
A rule that cannot be violated by database users.
Need for Explicit Backup and Recovery (Costs and Risks of the Database Approach)
A shared corporate database must be accurate and available at all times
Organizational Conflict (Costs and Risks of the Database Approach)
A shared database requires a consensus on data definitions and ownership, as well as responsibilities for accurate data maintenance
DBMS
A software system that is used to create, maintain, and provide controlled access to user databases
Design- Physical Database Design and Definition (SDLC)
An analyst decides on the organization of physical records, the choice of file organizations, the use of indexes, and so on (physical schema)
database application
An application program (or set of related programs) that is used to perform a series of database activities (create, read, update, and delete) on behalf of database users.
Agile Software Development
An approach to database and software development that emphasizes "individuals and interactions over processes and tools, working software over comprehensive documentation, customer collaboration over contract negotiation, and response to change over following a plan."
prototyping
An iterative process of systems development in which requirements are converted to a working system that is continually revised through close work between analysts and users.
Database
An organized collection of logically related data
Planning (SDLC)
Analysts review current databases and information systems; analyze the nature of the business area that is the subject of the development project; and describe, in general terms, the data needed for each information system under consideration for development
Excessive Program Maintenance (Disadvantages of File Processing Systems)
As much as 80% of the total information system's development budget might be devoted to program maintenance in file process systems
Improved Data Sharing
Authorized internal and external users are granted permission to use the database, and each user (or group of users) is provided one or more user views into the database to facilitate this use
Improved Data Consistency (Advantages of the Database Approach)
By eliminating or controlling data redundancy, we greatly reduce the opportunities for inconsistency
conceptual schema
Combines the different external views into a single, coherent, and comprehensive definition of the enterprise's data; represents the view of the data architect or data administrator
Application Programs
Computer-based application programs are used to create and maintain the database and provide information to users
Design- Logical Database Design (SDLC)
Conceptual schema is transformed into a logical schema, which describes the data in terms of the data management technology that will be used to implement the database; Then transform the combine data specifications into basic elements following well-established rules (rules come from relational database theory and normalization) (logical schema)
internal schema
Consists of two separate schemas: logical and physical; logical schema is the representation of data for a type of data management technology; physical schema describes how data are to be represented and stores in secondary storage using a particular DBMS
Components of the Database Environment
Data Modeling Design Tools Repository DBMS Database Application Programs User Interface Data and database administrators System developers End Users
Traditional File Processing
Data was stored in independent files without regard to other needs for that data (file processing systems)
improved data quality (Advantages of the Database Approach)
Database designers can specify integrity constraints that are enforced by the DBMS; one of the objectives of a data warehouse environment is to clean up operational data before they are place in the data warehouse
Which notation represents a relationship?
Diamond with a verb, first letter captial
Duplication of Data (Disadvantages of File Processing Systems)
Different systems/programs have separate copies of the same data
Limited Data Sharing (Disadvantages of File Processing Systems)
Each application has its own private files, and users have little opportunity to share data outside their own applications
Lengthy Development Times (Disadvantages of File Processing Systems)
Each new application requires that the developer essentially start from scratch by designing new file formats and descriptions and then writing the file access logic for each new program
According to the ER diagram, which is correct? Employees (0,1)> (1,1) Parking Space
Employee is optional for Parking Space; Parking Space is mandatory for Employee
New, Specialized Personnel (Costs and Risks of the Database Approach)
Frequently, organizations that adopt the database approach need to hire or train individuals to design and implement databases, provide database administration services, and manage a staff of new people
The process of defining a more general entity type from a set of more specialized entity type sif called
Generalization
planned data redundancy (Advantages of the Database Approach)
Good database design attempts to integrate previously separate (and redundant) data files into a single, logical structure
User Interface
Includes languages, menus, and other facilities by which users interact with various system components, such as data modeling and design tools, application programs, the DBMS, and the repository
Costs and Risks of the Database Approach
New, specialized personnel Installation and management cost and complexity Conversion costs Need for explicit backup and recovery Organizational conflict
Which ER diagram notation below represents a primary key?
Oval with name in it, capital first letter, under-lined
The enhanced ER diagram below represents the constraints?(one line, o)
Partial specialization and overlap rule
System Developers
Persons such as systems analysts and programmers who design new application programs
End users
Persons throughout the organization who add, delete, and modify data in the database and who request or receive information from it.
Data/Database Administrators
Persons who are responsible for overall management of data resources in an organization
Steps of the Systems Development Life Cycle (SDLC)
Planning Analysis Design Implementation Maintenance
Disadvantages of File Processing Systems
Program-Data Dependence Duplication of Data Limited Data Sharing Lengthy Development Times Excessive Program Maintenance
Advantages of the Database Approach
Program-data independence Planned data redundancy Improved data consistency Improved data sharing Increased application development productivity Enforcement of standards Improved data quality Improved data accessibility and responsiveness Reduced program maintenance Improved decision support
Which notation below represents an entity?
Rectangle with singular noun, all capital
________ is the most common database, also the type of database we will concentrate on
Relational database
Which of the following development process we draw a type of pictures called Entity-Relationship diagram for databases?
Requirement analysis
Data modeling and design tools
Software tools that provide automated support for creating data models.
The process of defining one or more subtypes of the supertype is called ______
Specialization
Physical Schema
Specifications for how data from a logical schema are stored in a computer's secondary memory by a database management system (Design- Physical Database Design)
Which ER diagram contains a "one-to-many" relationship?
Student (1,1) > (1,N) Adviser and Student (0,1) > (0,N) Adviser and Student (1,N) > (0,1) Adviser
Which relationship below represents (needs to be converted to) an associative entity?
Student (1,N) > (0, N) Course
Which ER diagram below represents a scenario in which "students at UofA must have one program adviser; but an adviser can mentor multiple students?"
Student (1,N)> (1,1) Adviser
Analysis (SDLC)
The analyst produces a detailed data model that identifies all the organizational data that must be managed for this information system (conceptual schema)
Program-data dependence (Disadvantages of File Processing Systems)
The close relationship between data stored in files and the software programs that update and maintain those files. Any change in data organization or format requires a change in all the programs associated with those files.
Maintenance (SDLC)
The designer adds, deletes, or changes characteristics of the structure of a database in order to meet changing business conditions, to correct errors in database design , or to improve the processing speed of database applications
Enterprise data modeling
The first step in database development, in which the scope and general contents of organizational databases are specified.
Logical Schema
The representation of a database for a particular data management technology (Design- Logical Database Design)
Program-Data Independence (Advantages of the Database Approach)
The separation of data descriptions (metadata) from the application programs that use the data
Conversion Costs (Costs and Risks of the Database Approach)
The term legacy system is widely used to refer to older applications in an organization that are based on file processing and/or older database technology
Systems Development Life Cycle (SDLC)
The traditional methodology used to develop, maintain, and replace information systems.
A binary relationship means _____
There are two entities connected by the relationship
The enhanced ER diagram below represents the constraints? (double line, o)
Total specialization and overlap rule
enforcement of standards (Advantages of the Database Approach)
When the database approach is implemented with full management support, the database administration function should be granted single-point authority and responsibility for establishing and enforcing data standards
improved data accessibility and responsiveness (Advantages of the Database Approach)
With a relational database, end users without programming experience can often retrieve and display data, even when they cross traditional departmental boundaries
implementation (SDLC)
a designer writes, tests, and installs the programs/scripts that access, create, or modify the database
user view
a logical description of some portion of the database that is required by a user to perform some task
increased productivity of application development (Advantages of the Database Approach)
a major advantage of the database approach is that it greatly reduced the cost and time for developing new business applications
entity
a person, a place, an object, an event, or a concept in the user environment about which the organization wishes to maintain data
database management system (DBMS)
a software system that is used to create, maintain, and provide controlled access to user databases
Data management is _____
at the heart of any organization that wants to survive in the global arena
Metadata
data that describes the properties and characteristics of end-user data and the context of those data
information
data that has been processed in such a way as to increase the knowledge of the person who uses the data
If an instance can belong to two (or more) subtypes, this describes the constraint of ______
disjoint rule
In the three-schema architecture, the view of end users is called _____
external schema
A non-database way of capturing data is ________
file based system
data model
graphical systems used to capture the nature and relationships among data
improved decision support
some databases are designed expressly for decision support applications
reduced program maintenance (Advantages of the Database Approach)
stored data must be changed frequently for a variety of reasons: new data item types are added, data formats are changed, and so on
data
stored representations of objects and events that have meaning and importance in the user's environment
data independence (Advantages of the Database Approach)
the separation of data descriptions from the application programs that use the data
external schema
the view (or views) of managers and other employees who are the database users; can be represented as a combination of detailed (or bottom-up) user views
