Map data structure in pl/sql for storing key value pair?

Is there anyway to create a map data structure in开发者_JAVA百科 pl/sql.

There is the PL/SQL associative array

DECLARE
  TYPE salary_tab_t IS TABLE OF NUMBER INDEX BY VARCHAR2(30);
  salary_tab salary_tab_t;
BEGIN
  salary_tab('JONES') := 10000;
  salary_tab('SMITH') := 12000;
  salary_tab('BROWN') := 11000;
END;

You can loop through the elements like this:

  l_idx := salary_tab.FIRST;
  LOOP
    EXIT WHEN l_idx IS NULL;
    dbms_output.put_line (salary_tab(l_idx));
    l_idx := salary_tab.NEXT(l_idx);
  END LOOP;