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In a digital transmission, the sender clock is 0.2 percent faster than the receiver clock.

How many extra bits per second does the sender send if the data rate is I Mbps?

Using the Employee table below, write the rational schema and draw it’s dependency diagram. Identify  all dependencies.  

EMP_NO 

EMP_NAME 

CUST_NO 

CUST_NAME 

CUST_PHONE 

PROD_NO 

PROD_NAME 

DATE

215 

SPHELELE 

15 

HUGUETTE 

0834528787 

10 

SOAP 

20/03/2012

216 

BOKHOSI 

16 

TANDIWE 

0784521635 

12 

BRAID 

20/03/2012

217 

THEMBA 

16 

TANDIWE 

0784521635 

15 

PHONE 

21/04/2012

218 

LEFA 

14 

BUSISIWE 

0618578542 

12 

PEN 

22/04/2012

219 

VALENTINE 

14 

BUSISIWE 

0618578542 

13 

LAPTOP 

22/04/2012

220 

PROMISE 

18 

GIRLY 

0829687841 

13 

LAPTOP 

22/04/2012

4.1 Identify all dependencies. (8) 

4.2 Using the Employee table above, write the rational schema and draw it’s dependency   diagram. (9) 

1. If you were designing a Web-based system to make airline reservations and sell airline tickets,

a. Which DBMS architecture would you choose from and why?

b. Why would the other architectures not be a good choice?

2. Design a database for an airline. The database must keep track of customers and their reservations, flights and their status, seat assignments on individual flights, and the schedule and routing of future flights. Your design should include an E-R diagram, a set of relational schemas, and a list of constraints, including primary-key and foreign-key constraints.

1. Consider the relations

Lecturer (firstName, lastName, email,course)

i. Print all the information about lecturers who handles DBMS

ii. Print the names and emails of those lecturers who take HCI

iii. Find the lecturer with the surname “feel free “and also handles “DBMS”

b) Use the schema below to express the following queries using Relational Algebra Research_Student(Name, Grad_Univ, CGPA, Age, Email) 

i. Find all research students who have their CGPA is greater than 3.5 and their ages of greater than 25 years.

ii. Find the names and emails of research students who have their CGPA less than 2.5

Question 2

A. Using the right integrity rules, explain why it is important to control how data is deleted from relational database. [10 Marks]

B. In your own words, explain why one cannot consider every table as a relation. [10 Marks]

C. All relations are in 1st Normal form. Explain.

Question 1

A. Jacobson has been given a project to design relational database for a company. He intends to start with logical design instead of conceptual design. What problems are likely to arise if the logical design of the relational database is created?

B. Suggest appropriate strategy one can use to address the problems that would arise as a result of starting the database design from logical design. Explain the process to get the issues resolved to satisfy certain constraints.

Question 2

A. Using the right integrity rules, explain why it is important to control how

  data is deleted from relational database.

B. In your own words, explain why one cannot consider every table as a

relation. [10 Marks] C. All relations are in 1st Normal form. Explain. 

•Consider the following scenario

•A company provides catering services for clients who need special-occasion, celebratory dinners. For each dinner, a number of dishes are to be offered. The dinner will be held at a venue. The company will provide staff to serve meals at the venue.

•The company needs a database to store data related to this business activity

–Identify a list of entities

–Identify pairs of entities where a direct relationship exist

–For each pair of relationship draw the entity relationship diagram justifying the choice of cardinalities.

define in detail datatypes in SQL server?

define variables in sql

Get the number of male and female premium users in the platform.

Expected Output Format

gendertotal_usersF...M