PL/SQL example

pkg.sql

-- sqlplus -s @ pkg.sql
set serverout on

create or replace package example
is
  procedure hello (thing in varchar2);
end example;
/

create or replace package body example
is
  procedure hello (thing in varchar2)
  is
    greeting varchar(8) := 'Hello ';
  begin
    dbms_output.put_line(greeting || thing);
  end hello;
end example;
/
show errors

execute example.hello('World');

begin
  example.hello('World');
end;
/

drop package example;
exit;