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3 years ago

How to represent derived attributes in database?

Computers and Technology

1 answer:

Vlad1618 [11]3 years ago

7 0

Answer:

Derived attribute can be defined as a type of attribute where its value will be derived from one or more of the other attributes of the same entity set.

Explanation:

An example of derived attribute is when we have an entity set called General. The set then has attributes like [Form], [Characteristics], [Address}, (Employment No).

(Employment No) which is represented distinctly in the attribute set can be called a derived attribute if it can be derived from one or more of the other attributes.

Derived attribute can be gotten through calculating values and not storing values.

For example, let us consider the following record of Teachers records;

(‘Teacher Number’, ‘Name’, ’Date of Birth’, Age today)

(‘E105’, ‘Samson’, ’07-Dec-1990’, 0)

This record shows that the teacher Samson was born on 7th of December, 1990. At the time of record insertion, he was born and 0 years old. What will be the value of his age on ’07-Dec-2000’? It is about 10 years. It clearly shows that the value is not fixed and it is a variable whenever the DOB is adjusted.

Therefore, we are not creating our table with derived attributes in it. Instead, the values ofderived attributes can be calculated at the time of retrieval and shown to the user. Hence, the record will look like as follows;

(‘E105’, ‘Samson’, ’07-Dec-1990’)

This means that 0 is a derived attribute from the Date of birth.

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A measure of technological evolution is the web year which is

olya-2409 [2.1K]

The correct answer is: <span>1/7 of a calendar year

</span>A Web year has been said to be the length of time it takes for Internet technology to evolve as much as technology in another environment might evolve in a calendar year. The term was coined at a time when the Internet and Web technology and culture were progressing at a phenomenal rate.

<span>The term is sometimes attributed to Lou Gerstner, then head of IBM. According to Larry Kunz, then the editor of IBM's Network Connection, the idea of a Web year was introduced by an unnamed female colleague in 1996. </span>

<span>In a 1996 interview in the WWW Journal, Tim Berners-Lee, chief inventor of the Web technologies, said: "What is a Web year now, about three months? And when people can browse around, discover new things, and download them fast, when we all have agents - then Web years could slip by before human beings can notice." When the interviewer suggested that such a pace would "take a physical toll" on people who work on the Web, Berners-Lee agreed that was true, but added that they would also "be able to live for three or four hundred Web years, which will be very exciting."</span>

7 0

3 years ago

Print the two strings in alphabetical order. Assume the strings are lowercase. End with newline. Sample output: capes rabbits im

ValentinkaMS [17]

Answer:

Following are the code to the given question:

import java.util.Scanner;//import package

public class OrderStrings // defining a class OrderStrings

{

public static void main(String[] args) //defining a main method

{

Scanner scnr = new Scanner(System.in);//defining a Scanner class object

String firstString;//defining a String variable

String secondString; //defining a String variable

firstString = scnr.next();//input value

secondString = scnr.next();//input value

if (firstString.compareTo(secondString) < 0)//use if to compare sting value

System.out.println(firstString + " " + secondString);//print sting value

else//else block

System.out.println(secondString + " " + firstString);//print sting value

}

Output:

rabbits capes

capes rabbits

Explanation:

In this code a class "OrderStrings" is defined inside the class the main method is defined that declares the two string variable that uses the input method to input the string value and after input, it uses the conditional statement. Inside this compareTo method is declared that compare string value and prints the string value.

4 0

3 years ago

According to symbolic interaction theory, the internet has helped to remove:

DanielleElmas [232]

Answer:

According to symbolic interaction theory, the internet has helped to remove:

(D) Time and space barriers.

Explanation:

The symbolic interaction theory is such theory which explains that language and symbols are the means of interaction in the social worlds. This theory tells us about the relationship between people in a society.
The option a is not correct as the internet has not remove the subculture rather it has provided safe space to it. Sub-culture refers to a group of special interest like group of a biker. Anyone can create their community on the internet.
The option b is also incorrect as internet has not remove interpersonal communication rather it has speed up this communication. It is a type of communication in which people communicate with each other via their expression of feelings, verbal and non-verbal means.
The option c is also incorrect as the inappropriate content has removed by internet rather now everyone can create content. But regulations and guidelines are being made. A lot of work has been to be done in this area.
The option d is correct as the internet has helped to remove the barriers of time and space. It has made this world a global village now anyone from any part of the world can talk to any person to other part of the world over the internet. They can create communities depending upon their interests. They can do business and many other things.

5 0

3 years ago

3. What workplace hazards can be found on picture A?

vekshin1

Answer:

<h2>Hakdog</h2>

Explanation:

<h3>kase hakdog ka kainin mo tite ko</h3>

8 0

3 years ago

Write a script that inputs a line of plaintext and a distance value and outputs an encrypted text using a Caesar cipher.

belka [17]

Answer:

def encrypt_text(text,value):

encoded = ""

for i in range(len(text)):

char = text[i]

if (char.isupper()):

encoded += chr"po"ord'po'char'pc' + value -65'pc' % 26 + 65'pc'

else:

encoded += chr'po'ord'po'char'pc' + value -97'pc' % 26 + 97'pc'

return encoded

plaintext = input("Enter sentence of encrypt: ")

dist_value = int(input("Enter number: "))

encrypted = encrypt_text(plaintext, dist_value)

print(encrypted)

Explanation:

The python program above is a Ceasar cipher implementation. The encrypt_text function is defined to accept text input and a distance value, which is used to encrypt the plaintext.

The user can directly input text and the distance value from the prompt and get the encrypted text printed on the screen.

7 0

3 years ago