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Margarita [4]
3 years ago
9

Define the terms candidate key and primary key. Explain the difference between a primary key and a candidate key.

Computers and Technology
1 answer:
Shkiper50 [21]3 years ago
5 0

Explanation:

Both Primary Key and Candidate Key are the attributes that are used to access tuples from a table. These (Primary key and Candidate key) are also can be used to create a relationship between two tables.

  • A Candidate Key can be any column or a combination of columns that can qualify as a unique key in the database. Each Candidate Key can qualify as a Primary Key.
  • A Primary Key is a column or a combination of columns that uniquely identify a record. The primary key is a minimal super key, so there is one and only one primary key in any relationship.

<em> The main difference between them is that a primary key is unique but there can be many candidate keys. </em>

I hope you find this information useful and interesting! Good luck!

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Explain about forensic tools?
Ganezh [65]

Answer:

 In the computer forensics, it basically examining the digital media by using the different types of specialist tools which is known as forensic tool.

It has the ability to acquiring the several evidence from the computer hard disk and by copying information, the data from the machine that can be procured and after that broke down for any data that is appropriate for the case.

There are different types of forensics tools that are:

  • SIFT (SANS Investigative Forensics Toolkit)
  • Volatility
  • Redline
  • Digitally forensics framework
  • COFEE

4 0
3 years ago
Write a loop that reads strings from standard input where the string is either "land", "air", or "water". The loop terminates wh
____ [38]

Answer:

count_land = count_air = count_water = 0

while True:

   s = input("Enter a string: ")

   if s == "xxxxx":

       break

   else:

       if s == "land":

           count_land += 1

       elif s == "air":

           count_air += 1

       elif s == "water":

           count_water += 1

print("land: " + str(count_land))

print("air: " + str(count_air))

print("water: " + str(count_water))

Explanation:

*The code is in Python

Initialize the variables

Create a while loop that iterates until a specific condition is met. Inside the loop, ask the user to enter the string. If it is "xxxxx", stop the loop. Otherwise, check if it is "land", "air", or "water". If it is one of the given strings, increment its counter by 1

When the loop is done, print the number of strings entered in the required format

4 0
3 years ago
Do all light bulbs server a practical purpose?
Greeley [361]

Answer:

A light bulb produces light from electricity

6 0
3 years ago
Modify the provided code file to create a workout tracking program that lets the user enter (from the console) the distance they
koban [17]

Answer:

  1. import java.util.Arrays;
  2. import java.util.Scanner;
  3. public class Main {
  4.    public static void main(String[] args) {
  5.        Scanner input = new Scanner(System.in);
  6.        double distances [] = new double[7];
  7.        for(int i=0; i < distances.length; i++){
  8.            System.out.print("Input running distance for day " + (i+1) + ": ");
  9.            distances[i] = input.nextDouble();
  10.        }
  11.        System.out.println(Arrays.toString(distances));
  12.    }
  13. }

Explanation:

The solution code is written in Java.

Firstly, create a Scanner object to get user input for running distance (Line 6). Next, declare a distances array and set the array size to 7 because we intend to use this array to hold running distance for 7 days per week.

Next, use the for loop that run for 7 times to repeatedly prompt user to input running distance for each day and store each value to the array distances (Line 9 -12).

At last, display the array to console terminal (Line 14).

3 0
3 years ago
Assume that speed = 10 and miles = 5. What is the value of each of the
Assoli18 [71]

a. speed + 12 - miles * 2  = 10 + 12 - 5 * 2. With order of operations, we do the multiplication first so the equation is now 10 + 12 - 10 = 22 - 10 = 12

b. speed + miles * 3  = 10 + 5 * 3 and again, order of operations gives us 10 + 15 = 25

c. (speed + miles) * 3  = (10 + 5) * 3 = 15 * 3 = 45

d. speed + speed * miles + miles  = 10 + 10 * 5 + 5 = 10 + 50 + 5 = 60 + 5 = 65

e. (10 – speed) + miles / miles = (10 - 10) + 5 / 5 = 0 + 5 / 5 = 5 / 5 = 1

5 0
3 years ago
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