Introduction
Define the following terms with example: i) Recursive Relationship, ii) Weak Entity type iii) Cardinality ratio iv) Ternary relationship
v) Metada
Metadata:The same entity type participates more than once in a relationship type in different roles.In such cases the role name becomes essential for distinguishing the meaning of each participation. Such relationship types are called recursive relationships.
An entity type may also have no key,in which case it is called a weak entity type.
cardinality ratio for a binary relationship specifies the number of relationship instances that an entity can participate in.
Relationship type of degree three is Ternary relationship.
The information stored in the catalog is called meta-data, and it describes the structure of the primary database.
Define Data-Independence? Discuss Types of it with 3-schema architecture.
Data Independence: The three-schema architecture can be used to explain the concept of data independence, which can be defined as the capacity to change the schema at one level of a database system without having to change the schema at the next higher level. We can define two types of data independence:
1.Logical data independence is the capacity to change the conceptual schema without having to change external schemas or application programs.
2 Physical data independence is the capacity to change the internal schema without having to change the conceptual (or external) schemas.
explain the components modules of DBMS and their interactions.
Database System Utilities
Common utilities have the following types of functions:
1.Loading:A loading utility is used to load existing data files—such as text files or sequential files—into the database.
2.Backup:A backup utility creates a backup copy of the database, usually by dumping the entire database onto tape.
3. File reorganization: This utility can be used to reorganize a database file into a different file organization to improve performance.
4. Performance monitoring: Such a utility monitors database usage and provides statistics to the DBA.
Mention Types of Attributes
Atomic/Single valued
Multivalued
Stored Vs Derived
Null Values
Attributes for Employee in an Organization
Name
SSN
Address
Phone
Department
Project
Dependent
Write queries in SQL for the following
a. Retrieve the name and address of all employees who work for the 'Research'department.
b. Show the resulting salaries if every employee working on the 'ProductX'project is given a 10 percent raise.
a. SELECT FNAME, LNAME, ADDRESS
FROM EMPLOYEE
WHERE DNO IN (SELECT DNUMBER
FROM DEPARTMENT
WHERE DNAME='Research’);
b. Show the resulting salaries if every employee working on the 'ProductX'project is given a 10 percent raise.
SELECT FNAME, LNAME, 1.1*SALARY
FROM EMPLOYEE, WORKS_ON, PROJECT
WHERE SSN=ESSN AND PNO=PNUMBER AND PNAME='ProductX’
What is a database?
a) Organized collection of information that cannot be accessed, updated, and managed
b) Collection of data or information without organizing
c) Organized collection of data or information that can be accessed, updated, and managed
d) Organized collection of data that cannot be updated
Which type of data can be stored in the database?
a) Image oriented data
b) Text, files containing data
c) Data in the form of audio or video
d) All of the above
Which of the following is not an example of DBMS?
a) MySQL
b) Microsoft Acess
c) IBM DB2
d) Google
Which of the following is a function of the DBMS?
a) Storing data
b) Providing multi-users access control
c) Data Integrity
d) All of the above
The ability to query data, as well as insert, delete, and alter tuples, is offered by ____________
a) TCL (Transaction Control Language)
b) DCL (Data Control Language)
c) DDL (Data Definition Langauge)
d) DML (Data Manipulation Langauge)
______________ is a set of one or more attributes taken collectively to uniquely identify a record.
a) Primary Key
b) Foreign key
c) Super key
d) Candidate key
Which forms have a relation that contains information about a single entity?
a) 4NF
b) 2NF
c) 5NF
d) 3NF
The traditional storage of data organized by the customer, stored in separate folders in filing cabinets is an example of ______________ type of ‘database’ management system.
a) Object-oriented database management system
b) Relational database management system
c) Network database management system
d) Hierarchical database management system
Which of the following is the best way to represent the attributes in a large db?
a) Dot representation
b) Concatenation
c) Relational-and
d) All of the mentioned
advantages of using the DBMS.
a) Controlling Redundancy
b)Restricting Unauthorized Access
Providing Persistent Storage for Program Objects and Data Structures
Permitting Inferencing and Actions Using Rules
Providing Multiple User Interfaces
Representing Complex Relationships Among Data
Enforcing Integrity Constraints
Providing Backup and Recovery
Additional Implications of the Database Approach