Nested Blocks : Nested Block « PL SQL Statements « Oracle PL/SQL Tutorial

1. Oracle PL/SQL Tutorial
2. PL SQL Statements
3. Nested Block

SQL>
SQL> --PL/SQL blocks can be nested, one inside the other.
SQL>
SQL> SET SERVEROUTPUT ON
SQL> DECLARE
  2    error_flag  BOOLEAN := false;
  3  BEGIN
  4    DBMS_OUTPUT.PUT_LINE('We are going to count from 100 to 1000.');
  5     DECLARE
  6       hundreds_counter  NUMBER(1,-2);
  7     BEGIN
  8       hundreds_counter := 100;
  9       LOOP
 10         DBMS_OUTPUT.PUT_LINE(hundreds_counter);
 11         hundreds_counter := hundreds_counter + 100;
 12         IF hundreds_counter > 1000 THEN
 13           EXIT;
 14         END IF;
 15        END LOOP;
 16     EXCEPTION
 17     WHEN OTHERS THEN
 18       error_flag := true;
 19     END;
 20     IF error_flag THEN
 21       DBMS_OUTPUT.PUT_LINE('Sorry, I cannot count that high.');
 22      ELSE
 23       DBMS_OUTPUT.PUT_LINE('Done.');
 24     END IF;
 25  END;
 26   /
We are going to count from 100 to 1000.
100
200
300
400
500
600
700
800
900
Sorry, I cannot count that high.

PL/SQL procedure successfully completed.

SQL>