Out VARCHAR2 parameters in PL/SQL

The PL/SQL takes the maximum size of output variable for VARCHAR2 from the calling block/procedure.

Consider the following example.

--

create or replace package test_pkg as

procedure test_val(i_num in number, o_expression out varchar2);

end test_pkg;
--

create or replace package body test_pkg as

procedure test_val(i_num in number, o_expression out varchar2) as

begin

  o_expression := LPAD('>', i_num);

end;

end;

--

declare

  l_expression VARCHAR2(5);

begin

  test_pkg.test_val(i_num => 5,

  o_expression => l_expression);

  dbms_output.put_line('Output:'||l_expression);

end;

Output: >

The value of l_expression is 5. so the maximum permissible size of o_expression is 5. If it increases as per the below execution, it will give an exception.

Error report:

ORA-06502: PL/SQL: numeric or value error: character string buffer too small

ORA-06512: at "DEMO.TEST_PKG", line 5

ORA-06512: at line 4

06502. 00000 - "PL/SQL: numeric or value error%s"

*Cause:

*Action: