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3 years ago

In this task, you will perform normalization on a crude table so that it could be stored as a relational database.

Computers and Technology

1 answer:

ryzh [129]3 years ago

5 0

Answer:

Check the explanation

Explanation:

(1.) The functional dependencies based on assumptions are as follows:-

Trip determines which staff was there in the trip, the car used for the trip, the quantity of fuel used in the trip, the fill up time and the total paid of the trip.

Service station refers to its address

Car details consist of the details of license plate, odometer reading and the fuel type used in the car

fuel type and the fill up time will help to determine the cost of the fuel at that time

cost of the fuel and the quantity of fuel used will determine the total paid

From the above assumptions the functional dependencies are as follows:-

Trip ID -> Staff Name, Car Details, Service Station, Quantity, Fill Up Time, Total Paid

Service Station -> Station Address,

Car Details -> License Plate, Odometer reading, Fuel Type

Fuel Type, Fill up Time -> Cost per litre

Cost per Litre, Quantity -> Total Paid

(2.) Initially the relation is as follows:-

R (Trip ID, Staff Name, Car Details, License Plate, Odometer Reading, Service Station, Station Address, Fill up Time, Fuel type, Quantity, Cost per Litre, Total Paid)

For 1 NF there should not be composite attributes,in the above relation Staff Name and Station Address are composite attributes therefore it will be decomposed as follows:-

R (Trip ID, Staff First Name,Staff Last Name, Car Details, License Plate, Odometer Reading, Service Station, Street, City, State, Zip Code, Fill up Time, Fuel type, Quantity, Cost per Litre, Total Paid)

For 2 NF there should not be partial dependency that is non prime attribute should not dependent upon any 1 prime attribute of candidate key, since in the given relation there is only 1 candidate key which is only Trip ID, therefore the relation is already in 2 NF.

For 3 NF there should not be transitive dependency that is non prime attribute should not dependent upon the other non prime attribute, if it is present then the relation will be decomposed into sub relations, the given relation is not in 3 NF therefore it will be decomposed as follows:-

R1 (Trip ID, Staff First Name, Staff Last Name, Car Details, Service Station, Quantity, Fill up time, Total paid)

R2 (Service Station, Street, City, State, Zip Code)

R3 (Car Details, License Plate, Odometer reading, Fuel Type)

R4 (Fuel Type, Fill up Time, Cost per litre)

R5 (Cost per Litre, Quantity, Total Paid)

(3.) After the 3 NF we add the primary and foreign key constraints as follows:-

R1 (Trip ID, Staff First Name, Staff Last Name, Car Details, Service Station, Quantity, Fill up time, Total paid)

R2 (Service Station, Street, City, State, Zip Code)

R3 (Car Details, License Plate, Odometer reading, Fuel Type)

R4 (Fuel Type, Fill up Time, Cost per litre)

R5 (Cost per Litre, Quantity, Total Paid)

In the above relational schema the primary keys are represented with bold and foreign keys by italic

(4.) The ER diagram of the above relational schema using crow's foot notation are as shown in the attached image below:-

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Write a for loop to print all elements in courseGrades, following each element with a space (including the last). Print forwards

ozzi

Answer:

The missing part of the code is:

for (i = 0; i < courseGrades.length; ++i) {

System.out.print(courseGrades[i]+" "); }

System.out.println();

for (i = courseGrades.length-1; i >=0 ; --i) {

System.out.print(courseGrades[i]+" "); }

System.out.println();

Explanation:

This iterates through the array

for (i = 0; i < courseGrades.length; ++i) {

This prints each element of the array followed by a space

System.out.print(courseGrades[i]+" "); }

This prints a newline at the end of the loop

System.out.println();

This iterates through the array in reverse

for (i = courseGrades.length-1; i >=0 ; --i) {

This prints each element of the array (reversed) followed by a space

System.out.print(courseGrades[i]+" "); }

This prints a newline at the end of the loop

System.out.println();

6 0

3 years ago

When creating a user generated function, what procedure is followed?

marin [14]

When creating a user-generated function, what procedure is followed d) all of the above.

<h3>What are the three factors of user-described characteristic?</h3>

A user-described characteristic has 3 essential additives which might be characteristic declarations, characteristic definition and characteristic called.

The characteristic prototypes are used to inform the compiler approximately the variety of arguments and approximately the specified datatypes of a characteristic parameter, it additionally tells approximately the go-back kind of the characteristic. By this information, the compiler cross-assessments the characteristic signatures earlier than calling.