Match each statement in Table 2 with its corresponding term in Table 1 and then
ID: 3866041 • Letter: M
Question
Match each statement in Table 2 with its corresponding term in Table 1 and then write the number of the corresponding term in column 3 of Table 2. Assume that you have been asked to develop a database application like blackboard, where student can access all the required material through the Internet. Would you use a centralized architecture, a 2-tier architecture or a 3-tier architecture? Clearly justify your choice (the reason for choosing that architecture and the reason(s) for not choosing the other two architectures).Explanation / Answer
a.
#
Statement
Term #
1
Collection of concepts that describes the structure, operation and constraints of a database
Data model
2
A composite attributes with uniqueness property
Super key
3
A person responsible for authorizing access to the database
DBA
4
Collection of related data
Database
5
Number of attributes in a relation
Degree
6
Changes when a data is updated or deleted or inserted in a database
Database state
7
Total number of row in a relation
Cardinality
8
Collection of programs which enables users to create and maintain database
DBMS
9
Database definition stored by the DBMS in the form of a database catalogue or dictionary
Meta-data
10
Specified between two relations to maintain the consistency among tuples of the two relations
Referential Integrity
B.
For developing the database application to students, for accessing all required materials through internet effectively, Three tier architecture can be suggested.
Two – tier architecture: it’s a client-server model. The systems are tightly coupled for the information sharing. When the users are increased performance will be degraded. In two –tier, it’s difficult to restrict the students from other websites.
Three-tier architecture: it is with three layers client, business, data layer. Client layer ,used for design purpose to present the data or to accept the input. Business layer, used as intermediate between the two layer. All business logic such as validation is processed in this layer. Data layer is an external resource such as database. In this model students will not have a direct access to the database.
Centralized architecture: all or most of the processing is performed on the central server. Performance will not be much better.
#
Statement
Term #
1
Collection of concepts that describes the structure, operation and constraints of a database
Data model
2
A composite attributes with uniqueness property
Super key
3
A person responsible for authorizing access to the database
DBA
4
Collection of related data
Database
5
Number of attributes in a relation
Degree
6
Changes when a data is updated or deleted or inserted in a database
Database state
7
Total number of row in a relation
Cardinality
8
Collection of programs which enables users to create and maintain database
DBMS
9
Database definition stored by the DBMS in the form of a database catalogue or dictionary
Meta-data
10
Specified between two relations to maintain the consistency among tuples of the two relations
Referential Integrity