Factorial of a number in PL/SQL

To calculate the factorial of a number using PL/SQL, you can make use of a simple iterative approach or a recursive method. Here, I'll demonstrate both approaches.

Iterative Approach:

DECLARE 
    n NUMBER := 5; -- Change this value for different results
    factorial NUMBER := 1;
    i NUMBER;
BEGIN 
    FOR i IN 1..n LOOP
        factorial := factorial * i;
    END LOOP;
    DBMS_OUTPUT.PUT_LINE('Factorial of ' || n || ' is: ' || factorial);
END;
/

Recursive Approach: To implement the recursive approach, you can define a function that calls itself. Here's an example:

DECLARE 
    FUNCTION factorial_recursive(n NUMBER) RETURN NUMBER IS
    BEGIN 
        IF n = 0 THEN
            RETURN 1;
        ELSE
            RETURN n * factorial_recursive(n-1);
        END IF;
    END factorial_recursive;

    num NUMBER := 5; -- Change this value for different results
BEGIN 
    DBMS_OUTPUT.PUT_LINE('Factorial of ' || num || ' is: ' || factorial_recursive(num));
END;
/

For both scripts, you can change the value of n or num to compute the factorial for a different number. However, be cautious with the recursive approach for larger values as it might exceed the maximum recursion depth. The iterative approach is generally more efficient for calculating factorial in such cases.

PL/SQL Procedure for Factorial Computation:

CREATE OR REPLACE PROCEDURE CalculateFactorial(p_number IN NUMBER) IS
    v_result NUMBER := 1;
BEGIN
    FOR i IN 1..p_number LOOP
        v_result := v_result * i;
    END LOOP;
    DBMS_OUTPUT.PUT_LINE('Factorial of ' || p_number || ' is: ' || v_result);
END;
/

PL/SQL Function for Factorial Computation:

CREATE OR REPLACE FUNCTION Factorial(p_number IN NUMBER) RETURN NUMBER IS
    v_result NUMBER := 1;
BEGIN
    FOR i IN 1..p_number LOOP
        v_result := v_result * i;
    END LOOP;
    RETURN v_result;
END;
/

PL/SQL Program to Find Factorial of a Given Number:

DECLARE
    v_number NUMBER := 5; -- Change this to the desired number
    v_result NUMBER;
BEGIN
    v_result := Factorial(v_number);
    DBMS_OUTPUT.PUT_LINE('Factorial of ' || v_number || ' is: ' || v_result);
END;
/

Oracle SQL Function for Finding Factorial:

Oracle SQL Query to Find Factorial of a Number:

WITH RecursiveFactorial AS (
    SELECT 5 AS n, 1 AS factorial
    FROM dual
    UNION ALL
    SELECT n - 1, factorial * (n - 1)
    FROM RecursiveFactorial
    WHERE n > 1
)
SELECT factorial
FROM RecursiveFactorial
WHERE n = 1;

Oracle SQL Script to Calculate Factorial:

DECLARE
    v_number NUMBER := 5; -- Change this to the desired number
    v_result NUMBER;
BEGIN
    SELECT factorial
    INTO v_result
    FROM (
        SELECT n, factorial
        FROM (
            SELECT LEVEL AS n, 1 AS factorial
            FROM dual
            CONNECT BY LEVEL <= v_number
        )
        CONNECT BY PRIOR n = n - 1
    )
    WHERE n = v_number;

    DBMS_OUTPUT.PUT_LINE('Factorial of ' || v_number || ' is: ' || v_result);
END;
/