FOR Loops
A FOR loop runs a predetermined number of times.
The syntax for a FOR loop is as follows:
FOR loop_variable IN [REVERSE] lower_bound..upper_bound LOOP
statements
END LOOP;
It says:
| Item | Description |
|---|---|
| loop_variable | the loop variable. The loop variable value is increased or decreased by 1 each time through the loop. |
| REVERSE | that the loop variable value is to be decremented each time through the loop. |
| lower_bound | the loop's lower boundary. |
| upper_bound | the loop's upper boundary. |
SQL> DECLARE
2 v_counter INTEGER;
3 BEGIN
4 v_counter := 0 ;
5 FOR v_counter IN 1..5 LOOP
6 DBMS_OUTPUT.PUT_LINE(v_counter);
7 END LOOP;
8 END;
9 /
1
2
3
4
5
PL/SQL procedure successfully completed.
SQL>
The following example uses REVERSE:
SQL> DECLARE
2 v_counter INTEGER;
3 BEGIN
4 v_counter := 0 ;
5 FOR v_counter IN REVERSE 1..5 LOOP
6 DBMS_OUTPUT.PUT_LINE(v_counter);
7 END LOOP;
8 END;
9 /
5
4
3
2
1
PL/SQL procedure successfully completed.
SQL>