Defaulting a null value in owa_util.ident_arr

   ident_arr is a type in OWA package.
   ...
   type ident_arr is table of varchar2(30) index by binary_integer;
   ...

   you just define a variable of type ident_arr. it will be null before you assign it.

   variable_name ident_arr;

     I do not think you need to default a null to a TYPE.

Sorry, I didn't specify... I want to default it to null as an IN variable:

CREATE OR REPLACE PROCEDURE ew_open_order_csv(selected_category in owa_util.ident_arr default empty,category_v in util.ident_arr default empty,org_v in number default null,subinv_v in varchar2 default null,cat_count_v in number default null)AS

Hold on... I think your right.