if you want more than on sys_context value, you would use an application context:


SQL> create or replace context my_ctx using my_proc
  2  /

Context created.

SQL> create or replace procedure my_proc( p_a in number, p_b in date, p_c in varchar2 )
  2  as
  3  begin
  4          dbms_session.set_context( 'my_ctx', 'a', to_char(p_a) );
  5          dbms_session.set_context( 'my_ctx', 'b', to_char(p_b,'yyyymmddhh24miss') );
  6          dbms_session.set_context( 'my_ctx', 'c', p_c );
  7  end;
  8  /

Procedure created.

SQL> create or replace view my_view
  2  as
  3  select sys_context( 'my_ctx', 'a' ) a,
  4         sys_context( 'my_ctx', 'b' ) b,
  5         sys_context( 'my_ctx', 'c' ) c
  6    from dual;

View created.

SQL> exec my_proc( 42, sysdate, 'hello world' );

PL/SQL procedure successfully completed.

SQL> select * from my_view;

A          B               C
---------- --------------- ---------------
42         20060503131617  hello world