1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
joja [24]
2 years ago
12

Why do relational databases use primary keys and foreign keys?.

Computers and Technology
1 answer:
Andrew [12]2 years ago
8 0

Answer:

Explanation:

A relational database is designed to enforce the uniqueness of primary keys by allowing only one row with a given primary key value in a table. A foreign key is a column or a set of columns in a table whose values correspond to the values of the primary key in another table.

You might be interested in
Access to sensitive or restricted information is controlled describes which of the key communications and information systems pr
Viktor [21]

Answer:

C: Security

Explanation:

Communications and information systems principles need to be, among other things, secure. They need to be able to protect sensitive information from those who intentionally not need to know. Some incident information like voice, networks, and data, are very sensitive and thus, should be secure to the right levels and should comply with privacy laws and data protection.

4 0
4 years ago
When should students in a study session use flash cards to quiz one another?
Lina20 [59]

When drilling, students in a study session use flashcards to quiz one another. thus, Option B is the correct statement.

<h3>What do you mean by drill and practice?</h3>

The term drill and practice can be described as a way of practice characterized by systematic repetition of concepts, examples, and exercise problems.

Drill and exercise is a disciplined and repetitious exercise, used as an average of coaching and perfecting an ability or procedure.

Thus, When drilling, students in a study session use flashcards to quiz one another. Option B is the correct statement.

Learn more about drill and practice:

brainly.com/question/27587324

#SPJ1

4 0
2 years ago
NEED HELP ASAP!
Marrrta [24]
Six inches is the answer
8 0
4 years ago
Two numbers are given (numbers are entered from the keyboard). If both numbers are positive, then output their sum, if both numb
AleksAgata [21]

Answer:

The program in Python is as follows:

num1 = int(input())

num2 = int(input())

if num1 >=0 and num2 >= 0:

   print(num1+num2)

elif num1 <0 and num2 < 0:

   print(num1*num2)

else:

   if num1>=0:

       print(num1**2)

   else:

       print(num2**2)

Explanation:

This gets input for both numbers

num1 = int(input())

num2 = int(input())

If both are positive, the sum is calculated and printed

<em>if num1 >=0 and num2 >= 0:</em>

<em>    print(num1+num2)</em>

If both are negative, the products is calculated and printed

<em>elif num1 <0 and num2 < 0:</em>

<em>    print(num1*num2)</em>

If only one of them is positive

else:

Calculate and print the square of num1 if positive

<em>    if num1>=0:</em>

<em>        print(num1**2)</em>

Calculate and print the square of num2 if positive

<em>    else:</em>

<em>        print(num2**2)</em>

3 0
3 years ago
g Suppose we want to compress a text consisting of 6 characters,a, b, c, d, e, fusingthe Huffman Algorithm. Give an example for
Papessa [141]

Answer:

e(a) = 0

e(b) = 10

e(c) = 110

e(d) = 1110

Explanation:

The Worst case will happen when f(a) > 2*f(b) ; f(b) > 2*f(c) ; f(c) > 2*f(d) ; f(d) > 2*f(e) and f(e) > 2*f(f).

Where f(x) is frequency of character x.

Lets consider the scenario when

f(a) = 0.555, f(b) = 0.25, f(c) = 0.12, f(d) = 0.05, f(e) = 0.02 and f(f) = 0.005

Please see attachment for image showing the steps of construction of Huffman tree:- see attachment

From the Huffman tree created, we can see that endcoding e() of each character are as follows:-

e(a) = 0

e(b) = 10

e(c) = 110

e(d) = 1110

e(e) = 11110

e(f) = 11111

So we can see that maximum length of encoding is 5 in this case.

3 0
3 years ago
Other questions:
  • The arrow next to All Programs indicates _____. that this item cannot be selected that this was the most recently used item the
    7·2 answers
  • Discuss the differences between dimensionality reduction based on aggregation and dimensionality reduction based on techniques su
    13·1 answer
  • Write the UPDATE command to increase the commission (column name :COMM) by 500 of all the salesman who have achieved sales (Colu
    15·1 answer
  • What action makes RAM on your computer disappear?
    12·2 answers
  • . A register in a computer has a of bits. How many unique combinations can be stored in the register?
    5·1 answer
  • Identify the independent and dependent variable in the statement: the number of hours studying for a class and the grade earned.
    12·1 answer
  • The words that follow a code number in the cpt manual are called the
    12·1 answer
  • If a person is proactive, they do NOT have to be defensive.<br> True<br> False
    9·2 answers
  • The one who will defeat me in this typing race I will mark the one brainliest:
    5·2 answers
  • You use lpstat and determine that a user named User1 has placed two large print jobs in the queue for Printer1 that have yet to
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!