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
lubasha [3.4K]
3 years ago
10

Consider the relation Courses(C, T, H, R, S, G), whose attributes can be thought of informally as course (C), teacher (T), hour

(H), room (R), student (S), and grade (G). Let the set of FD’s for Courses be C →T, HR →C, HT →R, HS →R, and CS →G.
Intuitively, the first says that a course has a unique teacher, and the second says that only one course can meet in a given room at a given hour. The third says that a teacher can be in only one room at a given hour, and the fourth says the same about students. The last says that students get only one grade in a course.
(a) What are all the keys for Courses?
(b) Verify that the given FD’s are their own minimal basis.
(c) Use the 3NF synthesis algorithm to find a lossless-join, dependency preserving decomposition of R into 3NF relations. Are any of the relations not in BCNF?
Computers and Technology
1 answer:
k0ka [10]3 years ago
3 0

Answer and Explanation:

a) Key for the relation courses is HS.

b) FD's are already minimal basis, as no attributes can be removed from the left side, right side is having only single attributes and none of the FD can be removed as given in the question.

c) By using the 3NF synthesis algorithm, the final set of relations obtained will be CT, HRC, HTR, HSR, CSG (FD'S are already proved to be minimal basis in part (b)). All the relations are in BCNF.

You might be interested in
Briefly explain specialisation?​
Jlenok [28]

Answer:

b

Explanation:

4 0
3 years ago
Convert 30 to hexadecimal ​
Delvig [45]

Answer:

1E

Explanation:

Here is a table to help you. Similar to a multipication table, just follow either the number 3 down to A (aka 10) or 6 x 5 and you will find your answer of

1E = 30

6 0
3 years ago
Traceability of requirements is helpful in the followingexcept
larisa86 [58]

Answer: D)  Identifying GUI's for a particular requirement

Explanation:

 Traceability of requirements is helpful except identifying GUI's for a particular requirements as, traceability in project management describe the relationships between two or more element throughout in the development process and outline the relationship between the customer requirement by traceability matrix. And the requirement of traceability is so important because it creating a downstream flow of software and test cases in software requirement but not helpful in GUI identification.

6 0
3 years ago
Programming challenge description: Write a program that, given two binary numbers represented as strings, prints their sum in bi
Lubov Fominskaja [6]

Answer:

The program to this question can be given as:

Program:

#include<iostream>  //include header file

using namespace std;  

string add(string a, string b)  //define add function

{       //declare variable  

   string result = "";  

   int sum = 0,k,l;      

   cahr x;    

   k= a.size() - 1;

   l = b.size() - 1;  

   while (k>= 0 || l>= 0 || sum == 1) //loop

   {

   //addition 

       sum= sum+ ((k >= 0)? a[k] - '0': 0);  

       sum= sum+ ((l >= 0)? b[l] - '0': 0);

        x=sum%2;

      result=(x+'0') +result;

  // Compute carry

       sum =sum/ 2;  

       // Move to next digits  

       k--;  

       l--;  

   }  

   return result; //return value

}

int main()  //main method  

{  

   string a,b;  //string variable

   cout<<"Enter first binary digit: ";  //message.

   cin>>a;     //input from user

   cout<<"Enter Second binary digit: ";  //message.

   cin>>b;     //input from user

   cout <<"Addition :"<<add(a, b)<<endl; //print addition

   return 0;  

}

Output:

Enter first binary digit: 1101

Enter Second binary digit: 100

Addition :10001

Explanation:

In the above c++ program first, we include the header file. Then we define the add function in the add function we add two binary digits by passing value as arguments. In this function, we define a variable that is used on the addition of binary numbers. In this function we define the loop in the loop we check if two binary number is 1 then it will print 0 and pass 1 as the carry. after performing addition it will return value. In the main function, we take two binary numbers from the user and pass the value to the function and print function return value.

8 0
3 years ago
The _____ requirements are associated with the efficiency, maintainability, portability, reliability, reusability, testability,
melamori03 [73]

Answer: Non-functional

Explanation:

Non-functional requirement(NFR) are the the requirements that evaluates operation of any particular system.It consist of several factors for judging the system such as security, reliability, quality, utility, maintainability etc.These parameters depicts about how a system will perform the tasks.

Other options are incorrect because function requires are used for depicting about specific and certain function in system. Performance requirements deal with the parameter of operation execution.

Correctness and standard requirement are measure for correcting system and general needs in a system respectively.

7 0
3 years ago
Read 2 more answers
Other questions:
  • Learning about public speaking can help improve your ________________.
    15·1 answer
  • An example of software most commonly associated with productivity software is ____.
    12·1 answer
  • 1. [2 points] Write a function to compute the volume of a sphere, given its radius. 2. [2 points] Write a recursive function to
    7·1 answer
  • Write a class named Accumulator containing: An instance variable named sum of type integer. A constructor that accepts an intege
    14·1 answer
  • A(n) __________ item is a hardware or software item that is to be modified and revised throughout its life cycle
    10·1 answer
  • Michael needs to ensure that those items that are automatically archived are still easily accessible within Outlook. Which optio
    7·2 answers
  • WHAT DOES THE SCRATCH CODE BELOW DO?
    6·1 answer
  • Write a Coral program using integers userNum and x as input, and output userNum divided by x four times.
    7·1 answer
  • 50 ) What is the cell address of 4th row and 4th column? A) 4D B) E4 оооо C) 04 D) B4​
    9·1 answer
  • When an EC2 instance is being modified to have more RAM, is this considered Scaling Up or Scaling Out?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!