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