SQL>
SQL>
SQL> -- variable scope
SQL>
SQL> declare
2 parent_number number;
3 begin
4 -- parent_number is visible and in scope
5 parent_number := 1;
6
7 declare
8 child_number number := 2;
9 begin
10 -- child_number is visible
11 dbms_output.put_line('parent + child = ' ||
12 to_char(parent_number + child_number));
13 end;
14
15 -- child_number is now not visible nor in scope:
16 child_number := 2;
17 dbms_output.put_line(child_number);
18
19 end;
20 /
child_number := 2;
*
ERROR at line 16:
ORA-06550: line 16, column 5:
PLS-00201: identifier 'CHILD_NUMBER' must be declared
ORA-06550: line 16, column 5:
PL/SQL: Statement ignored
ORA-06550: line 17, column 26:
PLS-00201: identifier 'CHILD_NUMBER' must be declared
ORA-06550: line 17, column 5:
PL/SQL: Statement ignored
SQL>
SQL>
SQL>