rem *********************************************************
rem *     file: loop_ex1.sql
rem *     desc: This script contains an example of factorial
rem *           ( Ex: 6! = 1 * 2 * 3 * 4 * 5 * 6 )
rem *           calculation using Simple LOOP.
rem *           Simulation Repeat ... Until LOOP
rem *     args: none
rem *  created: by  N.Vorobyeva    date: Jan 25, 1998
rem *  modified: by               date:
rem *********************************************************

clear screen
set ver off
set echo off
set serveroutput on

/* These are SQL*Plus commands for doing I/O
   They're not part of PL/SQL itself, so you can't, e.g., use them
   inside a PL/SQL procedure. */
PROMPT Enter NUMBER to calculate a Factorial
ACCEPT v_limit

DECLARE
   v_counter    INTEGER := 1;
   v_factorial  NUMBER := 1;

BEGIN
   LOOP
    v_factorial := v_factorial * v_counter;

    DBMS_OUTPUT.PUT_LINE('Counter =  '||v_counter ||', Factorial =  '||v_factorial);
    v_counter := v_counter + 1;
    EXIT WHEN v_counter > &v_limit;
    /* v_limit is preceded by an ampersand because it's a SQL*Plus var,
       read in with above, not an ordinary PL/SQL var. */
   END LOOP;

   DBMS_OUTPUT.PUT_LINE('You''re out when counter = ' || v_counter);  -- control transferred here on exit

END;
/