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3 years ago

What is the difference between a key and a superkey?

Computers and Technology

1 answer:

netineya [11]3 years ago

4 0

Answer:

Answered below

Explanation:

A key is a single or combination of many attributes that enable us pull a row of data from a table. Keys are identifiers used to get data seamlessly from the database. A key can be a primary key, secondary key, control key, or super key. A super key is a key or set of attributes use to identify tuples in a database. It can contain extra attributes not necessary for uniquely identifying a database.

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Exercise : Randomizer In this exercise, we are going to create a static class Randomizer that will allow users to get random int

Nutka1998 [239]

Answer:

Here the code is by using java.

Explanation:

//Randomizer.java

public class Randomizer {

public static int nextInt() {

//get random number from 1-10

int randInteger = (int) (Math.random() * (11) + 1);

//if number is greater than 10 or less than 1

while (randInteger > 10 || randInteger < 1) {

randInteger = (int) (Math.random() * (11) + 1);

}

return randInteger;

}

public static int nextInt(int min, int max) {

//formula to get random number from min-max

int randInteger = (int) (Math.random() * (max + 1) + min);

while (randInteger > max || randInteger < min) {

randInteger = (int) (Math.random() * (max + 1) + min);

}

return randInteger;

}

//RandomizerTester.java

public class RandomizerTester {

public static void main(String[] args) {

System.out.println("Results of Randommizer.nextInt()");

for (int i = 0; i < 10; i++) {

System.out.println(Randomizer.nextInt());

}

int min = 5;

int max = 10;

System.out.println("\n Results of Randomizer.nextInt(5,10)");

for (int i = 0; i < 10; i++) {

System.out.println(Randomizer.nextInt(min, max));

}

OUTPUT:

Results of Randommizer.nextInt()

Results of Randomizer.nextInt(5,10)

4 0

2 years ago

Within the seven domains of a typical IT infrastructure, there are particular roles responsible for data handling and data quali

nikitadnepr [17]

Answer:

The answer is "auditors"

Explanation:

Description to this question can be described as follows:

Auditors are professionals who analyze business and corporate accounts to determine, that the financial reports are accurate and lawful. It will serve as a consultant to suggest possible measures for risk avoidance or cost reduction.
Data security is the mechanism to avoid theft, loss of sensitive information, and information quality is critical and it is not able to know or stay in contact with your clients without high-quality data, that's why auditors are the correct answer and other choices can't be defined in the following senior.

7 0

3 years ago

Assume that you have an ArrayList variable named a containing 4 elements, and an object named element that is the correct type t

jonny [76]

Answer:

Option (4) is the correct answer.

Explanation:

In Java programming language ,array collection starts from 0 index location and ends in a size-1 index location. So to access the last elements the user needs to use a[Size-1] statement. so to modify the value of the last location of the array the user needs to use "a[size-1]= element;".

But when the user wants to add some new value to the end of the array list collection then he needs to use the statement--

a.add(element); //where add is a function, element is a value and a is a array list object.

Another option is invalid because--

Option 1 is not the correct because "a[3]=element;" modify the value of the 3rd element of the array.
Option 2 gives a compile-time error because add functions bracts are not closed.
Option 3 gives the error because a[4] gives the location of the 5th element of the array but the above question says that a is defined with 4 elements.

7 0

2 years ago

Define each of the following data mining functionalities: characterization, discrimination, association and correlation analysis

Step2247 [10]

Answer:

In the clarification portion below, the definition according to the received information is summarized.

Explanation:

Characterization:

It is indeed a summary of general object characteristics in something like a target class and creates characteristic laws.

Discrimination:

Just before predefined data types have been held to a different standard from everyone else, it's indeed bias which always happens.

Association:

It's a mechanism that determines the possibility that objects in a set will co-occur.

Classification:

It is indeed duction which attributes elements to target groups or classes in a set.

Prediction:

It is solely dependent on either the interpretation of other similar values to classify data points.

Clustering:

It has been used to position the components of the information through their corresponding classes.

Evolution Analysis:

It would be for objects whose behavior varies throughout time to explain or design regularities.

5 0

3 years ago

What's exactly the difference between "Library" and "Framework" ?

Mariana [72]

Answer:

The key difference between a library and a framework is “Inversion of Control”. When you call a method from a library, you are in control. But with a framework, the control is inverted:the framework calls you

Explanation:

A library performs specific, well-defined operations.

A framework is a skeleton where the application defines the "meat" of the operation by filling out the skeleton. The skeleton still has code to link up the parts but the most important work is done by the application.

Examples of libraries: Network protocols, compression, image manipulation, string utilities, regular expression evaluation, math. Operations are self-contained.

Examples of frameworks: Web application system, Plug-in manager, GUI system. The framework defines the concept but the application defines the fundamental functionality that end-users care about.

8 0

2 years ago