consider the following tables pertaining to employees working for different Write the SQL statement to retrieve the average age of employees for each

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1 Midterm 1 In a company, each employee has the following attributes: ss#, name, age, salary. Each employee participates p in an advisor/advisee relationship with another employee. An advisor is also an employee of the company and have an advisor of his or her own. An advisor may advise several employees. However, each employee has at most one advisor. Draw the ER: 1

2 consider the following tables pertaining to employees working for different departments: Emp (SS#, name, age, salary, dno) Dept (dno, dname, floor, mgrss#) Write the SQL statement to retrieve the average age of employees for each department. 2

3 Consider the following relational database, where the primary keys are underlined. Give an expression in the relational algebra to express each of the following queries: employee(person-name, name street, city) Modify the database so that Jones now lives in Newtown 3

4 employee(person-name, street, city) Give all managers of First Bank Corporation a 10 percent raise Person-name=manager-name 4

5 Consider the following relational database, where the primary keys are underlined. Give an expression in the relational algebra to express each of the following queries: employee(person-name, name street, city) Find the names of all employees who work for First Bank Corporation. 5

6 Consider the following relational database, where the primary keys are underlined. Give an expression in the relational algebra to express each of the following queries: employee(person-name, name street, city) Find the names, street address, and cities of residence of all employees who work for First Bank Corporation and earn more than $10, per annum. 6

7 employee(person-name, street, city) SQL Find all employees in the database who earn more than each employee of Small Bank Corporation. Assumes that all people work for at most one company 7

8 employee(person-name, street, city) SQL Find all employees in the database who live in the same cities and on the same streets as do their managers. 8

9 employee(person-name, street, city) SQL Give all employees of First Bank Corporation a 10-percent raise. UPDATE works SET salary = salary * 1.1 WHERE company-name = FBC 9

10 A disk drive is a mechanical device. When this device is activated to read a disk page, pg it typically yincurs the overhead of a seek time, rotational latency, and a transfer time. Define the meaning of each term? 10

11 Provide a definition of a primary and a candidate key. What is the difference between these two concepts. 11

12 Describe the indexed heap organization of records on a disk page. Draw a picture to demonstrate the organization of records on a disk page 12

13 Consider the relation scheme and FD shown below. Programming-Task(Programmer-ID, Programming-Package-ID, Programming-Package-Name, Total-Hours-Worked-on-Package) Programming-Package-ID Programming-Package-Name What is the highest normal form of this relation? Transform this relation to its next higher form Can the information of the given relation be recovered? What operation is necessary to recover it? 13

Northern India Engineering College, New Delhi Question Bank Database Management System. B. Tech. Mechanical & Automation Engineering V Semester

Northern India Engineering College, New Delhi Question Bank Database Management System. B. Tech. Mechanical & Automation Engineering V Semester 1. List four significant differences between a file-processing system and a DBMS. 2. Explain the difference between physical and logical data independence. 3. What are five main functions of a database