Identifiers defined in the declaration of the child block are only in scope and visible within the child block itself. : Variable Scope « PL SQL « Oracle PL / SQL






  1. Oracle PL / SQL
  2. PL SQL
  3. Variable Scope

Identifiers defined in the declaration of the child block are only in scope and visible within the child block itself.

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


SQL>
SQL>








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