Print all the prime numbers between ‘m’ and ‘n’ in PL/SQL

Prerequisite – PL/SQL Introduction

In PL/SQL code groups of commands are arranged within a block. A block group related declarations or statements. In declare part, we declare variables and between begin and end part, we perform the operations.

Problem :
Write a script in PL/SQL to display all the prime numbers between any two positive whole numbers.

Explanation :
Here, all the prime numbers between any two numbers taken as input as the upper limit and the lower limit are returned.A prime number is a natural number greater than 1 that cannot be formed by multiplying two smaller natural numbers.

In this implementation, the number of divisors of a number that occurs between the two limits is counted which should be 2 (1 and the number itself). If the number of divisors is 2, then that number is returned.

For example, consider the number 5. It has only two divisors: 1 and the number 5 itself.
Hence, it is a prime number.

Examples :

Input: 10  20
Output: 11 13 17 19

Input: 20  30
Output: 23 29  

Below is the implementation :

DECLARE
--the upper limit and the lower limit are taken as user inputs.
   low number(2);
   high number(2);
   n number(2);
   m number(2);
   c number(20);
BEGIN
   dbms_output.put_line('Enter the lower and higher limit:');
   low:=&low;
   high:=&high;
--The main operation happens in this loop
  for n IN low.. high
    loop
       c:=0;
       for m IN 1.. n
         loop
           if mod(n, m)=0 then
             c:=c+1;
            end if;
            end loop;
--the number of divisors for each number in the range is counted and then checked.
            if c<=2 then
               dbms_output.put_line(n||'\n');
            end if;
         end loop;

END;

Output :

Input: 
Enter the lower and higher limit:1  10
Output: 2
        3
        5
        7