##  Examples of package variable "constants".


    PACKAGE FIXED
    AS
      sex             varchar2(1);
      --
      male            constant fixed.sex%type := ‘M’;
      female          constant fixed.sex%type := ‘F’;
      --
      true            constant number(1)      := 1;
      false           constant number(1)      := 0;
      min_school_age  constant number(2)      := 5;
      max_child_dep   constant number(12)     := 29,490;
    END;


    DECLARE
      sex   fixed.sex%type;
    BEGIN
      if :tot_sal <= fixed.max_child_dep then
         select count(decode(C.gender, fixed.male,  'x','')),
                count(decode(C.gender, fixed.female,'x',''))
         into   :tot_males, :tot_females
         from   emp_children C
         where  C.age >= fixed.min_school_age;
      else
         ....
      end if;
    END;