The SQL is used to change a table's structure by:
The use of the SQL ALTER TABLE command.
<h3>How is it done?</h3>
The SQL ALTER TABLE command is known to be that which is often used to alter the structure of an existing table.
It is known to help one to be able to add or delete columns, make or destroy indexes, alter the kinds of existing columns, rename columns or the table itself.
Note that It can also be used to alter the comment for any kind of table and type of the table therein.
Learn more about SQL from
brainly.com/question/25694408
#SPJ1
Answer:
import java.util.Scanner;
public class DashLine {
public static void main(String[] args) {
// Declaring variables
int n;
/*
* Creating an Scanner class object which is used to get the inputs
* entered by the user
*/
Scanner sc = new Scanner(System.in);
// Getting the input entered by the user
System.out.print("Enter a number :");
n = sc.nextInt();
// calling the method by passing the user entered input as argument
dashedLine(n);
}
//This method will print the dashed line for number greater than zer
private static void dashedLine(int n) {
if (n > 0) {
for (int i = 1; i <= n; i++) {
System.out.print("-");
}
System.out.println();
}
}
}
Explanation:
Answer:
See explaination
Explanation:
Somehing is considered functional dependent (FD) if a relationship between two attributes, typically between the PK and other non-key attributes within a table. For any relation R, attribute Y is functionally dependent on attribute X (usually the PK), if for every valid instance of X, that value of X uniquely determines the value of Y.
Please kindly check attachment for the other details.
The answer & explanation for this question is given in the attachment below.
Answer:
b. foreign key
Explanation:
In the database world, a foreign key is a field on one table and a primary key for another table. The purpose of a foreign key is to provide linkages between two or more tables. Given two tables A and B, and making A the point of reference, a primary key is a field that is unique in A while a foreign key is unique in B.
On another hand, a composite primary key is a combination of two or more fields/columns on database table that can be used to uniquely identify each row in the table.
In the database lingua, what we have is a unique key not a distinct key, though the two words are similar in meaning.
A duplicate key is used when an information may be repeatedly entered on a table.
So the correct option is a foreign key.