1. What are the main differences between a file-processing system and a database management system?
Ans: A database management system coordinates both the physical and the logical access to the data, whereas a file-processing system coordinates only the physical access.
2. What are the major advantages of a database system? What are the major
Disadvantages of a database system?
a) Controlling Data redundancy
b) Data Consistency
c) Data Sharing
a) Cost of hardware and software
b) Cost of data sharing
c) Database Failures
3. Identify some informal queries and update operations that you would expect to apply
to the database shown in Figure 1.2.?
Ans: The database has shown the student information for smith and brown. It also represents the course details. Then it shows the intake of the ...view middle of the document...
List the responsibilities of the database manager. For each responsibility, explain
those problems that would arise if the responsibility were not met?
Ans: responsibilities of data manager:
a) Interaction with the file manager
b) Integrity enforcement
c) Security reinforcement
d) Backup and recovery
If these responsibilities were not met by a given DBM, the following problems can occur
a) If there is no manager interaction then nothing stored in the files can be retrieved.
b) Consistency constrains may not be satisfied, account balances could be low the minimum allowed, employees can earn more in overtime
c) Unauthorized users may access the database.
d) Data could be lost permanently
6. What are the main functions of a database administrator?
Ans: A database administrator (DBA) is an IT professional responsible for the installation, configuration, upgrading, administration, monitoring, maintenance, and security of databases in an organization.
a) Managing data security and privacy
b) Managing Data Integrity
c) Installing and upgrading the database server and application tools
d) Allocating system storage and planning future storage requirements for the database system.
e) Controlling and monitoring user access to the database
7. Discuss the main categories of data models. What are the basic differences between
the relational model, the object model, and the XML model?
Ans: Data Model can be defined as an integrated collection of concepts for describing and manipulating data, relationships between data, and constraints on the data in an organization.
There have been many data models proposed in the literature. They fall into three broad categories:
a) Object Based Data Models. Examples • Entity-Relationship • Object Oriented • Semantic • Functional
b) Physical Data Models
c) Record Based Data Models. Examples:- • Hierarchical Model • Network Model • Relational Model