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3 years ago

What is database design?

1 answer:

3 0

Answer: Database design is the model created of data/information for any particular organization .the relation between the information and which data is to be stored is the most important factor for designing .These parameters are decided by the designer of the database.

After the decision of the designed the data is invoked in the database .The data representation in the theoretical manner is known as ontology.The classification and relation defining is the purpose of the database design.

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What is the decimal number 75 in binary and hexadecimal?

hammer [34]

Answer:

00110111 00110101-Binary

3735-Hex

8 0

3 years ago

In this assignment, you will design and create an ArrayList-based application that manages a collection of DVDs. Information abo

sergij07 [2.7K]

Create and design an arraylist based application which manages a DVDs collection.

Explanation:

DVD movie consists of a title, a rating (e.g. PG, R, etc.), and a running time in minutes.

In this project, you will create an application to allow the user to maintain a collection of DVD movies using an array.

When the application starts up, it will read in the DVD data from a text file to initialize the array, if the file is available. If the file is not there, then the program starts with an empty array. If the file is corrupted (has an invalid or missing value), then the program stops its initialization at the point of the error. The data file should contain one DVD per line, with title followed by rating followed by running time in minutes, all separated by commas. You may assume titles are all in uppercase and do not contain commas. For example:

ANGELS AND DEMONS,PG-13,138

STAR TREK,R,127

UP,PG,96

The titles may not be in alphabetical order, but the DVDs should be inserted into the array in alphabetical order.

The application will then allow its user to perform the following operations:

ADD OR MODIFY DVD - The user will be prompted to enter the title, rating and running time (in minutes) for a DVD. If the title is already in the array, then the rating and running time are updated to the supplied values. If the title is not in the array, a DVD is added to the array so that the array is sorted by title. Convert all titles to uppercase only.

REMOVE DVD - The user will be prompted to enter the title of a DVD. If the title is in the array, then the DVD is removed, shifting subsequent DVDs over one position to fill in the gap left by the removed DVD. Again, titles must match exactly (in uppercase).

GET DVDs BY RATING - The user will be prompted to enter a movie rating (e.g. PG). This operation displays a string containing all DVDs matching the given rating in the order that they appear in the DVD collection, separated by newline characters.

GET TOTAL RUNNING TIME - This operation displays the total running time of all DVDs in the collection for the user.

SAVE & EXIT - The user can quit the program, performing an automatic save if the DVD collection has been modified.

Java Files

DVD.java - A class to model a single DVD, including its title, rating and total running time.

DVDCollection.java - A class to model a collection of DVDs using an array.

DVDUserInterface.java - An interface that describes the operation required for any user interface to this DVD collection.

DVDGUI.java - A class that implements the DVDUserInterface interface and provides a graphical user interface to the DVD collection.

DVDConsoleUI.java - A class that implements the DVDUserInterface interface and provides a console user interface to the DVD collection.

DVDManager.java - A class that contains a main method that launches one of the two user interfaces for the user to work with the DVD collection based on the user input.

Complete the DVD class by completing the given methods (constructor, accessors and mutators). Add javadoc comments so you can generate a javadoc documentation file showing how to use this class.

The DVDCollection class uses an array to maintain the collection of DVDs. The DVDs should be stored in alphabetical order based on title starting at position 0 in the array, using adjacent cells. All titles should be stored in uppercase only and are assumed to be unique (no duplicates).

toString - returns a string containing all of the DVDs in the collection, separated by newlines characters, along with the value of numdvds and the length of the DVD array for debugging purposes. The string should be formatted as shown in the example below:

numdvds = 3

dvdArray.length = 7

dvdArray[0] = ANGELS AND DEMONS/PG-13/138min

dvdArray[1] = STAR TREK/R/127min

dvdArray[2] = UP/PG/96min

addOrModifyDVD - given the title, rating and running time of a DVD, add this DVD to the collection if the title is not present in the DVD collection or modify the DVD's rating and running time if the title is present in the collection.insert the DVD so that all DVDs are in alphabetical order by title.

removeDVD - given the title, this method should remove the DVD with this title from the collection if present. The title must match exactly (in uppercase). If no title matches, do not change the collection.

getDVDsByRating - given the rating, this method should return a string containing all DVDs that match the given rating in the order that they appear in the collection, separated by newlines.

getTotalRunningTime - this method should return the total running time of all DVDs in the collection. If there are no DVDs in the collection, return 0.

loadData - given a file name, this method should try to open this file and read the DVD data contained inside to create an initial alphabetized DVD collection.

save - save the DVDs currently in the array into the same file specified during the load operation, overwriting whatever data was originally there.

7 0

3 years ago

The source Host A is going to send 5KB (5120byte) of data to the destination Host B over an established TCP connection, which ha

NISA [10]

Answer:

the answer is d have a nice day

Explanation: i got a 100

3 0

2 years ago

Write a program that reads in an integer value for n and then sums the integers from n to 2 * n if n is nonnegative, or from 2 *

devlian [24]

Answer:

Following are the program in c++

First code when using for loop

#include<iostream> // header file

using namespace std; // namespace

int main() // main method

{

int n, i, sum1 = 0; // variable declaration

cout<<"Enter the number: "; // taking the value of n

cin>>n;

if(n > 0) // check if n is nonnegative

{

for(i=n; i<=(2*n); i++)

{

sum1+= i;

}

else // check if n is negative

{

for(i=(2*n); i<=n; i++)

{

sum1+= i;

}

cout<<"The sum is:"<<sum1;

return 0;

Output

Enter the number: 1

The sum is:3

second code when using while loop

#include<iostream> // header file

using namespace std; // namespace

int main() // main method

{

int n, i, sum1 = 0; // variable declaration

cout<<"Enter the number: "; // taking the value of n

cin>>n;

if(n > 0) // check if n is nonnegative

{

int i=n;

while(i<=(2*n))

{

sum1+= i;

i++;

}

else // check if n is negative

{

int i=n;

while(i<=(2*n))

{

sum1+= i;

i++;

}

cout<<"The sum is:"<<sum1;

return 0;

}

Output

Enter the number: 1

The sum is:3

Explanation:

Here we making 2 program by using different loops but using same logic

Taking a user input in "n" variable.

if n is nonnegative then we iterate the loops n to 2 * n and storing the sum in "sum1" variable.

Otherwise iterate a loop 2 * n to n and storing the sum in "sum1" variable. Finally display sum1 variable .

4 0

3 years ago

Given the variables full_admission_price and discount_amount (already defined), write an expression corresponding to the price o

stiks02 [169]

Answer:

if full_admission_price = f and discount_amount = d

=> Price of a discount admission = d/f

total_weight

quantity

weight of one item = total_weight/quantity

for i in range(80, 18, -2):

print(i, end=' ')

Explanation:

The first two questions are just mathematical to get a single quantity given some relationship. So, its basically division

For the python code, I used the python's range function which takes in three arguments. The first one is the starting value, the second one is the terminating value which is the number before the terminating value and the last one specifies the common difference popularly known as step in the language. Since the step is 2, only even numbers are printed out. In the print function, I made use of the end keyword specifying a space (' ') as the end. This ensures that the print is done in the same line with a space seperating them. Without that specification, each result will printed in a newline

7 0

3 years ago