Bool support Oracle SQL
You can write your own wrapper like this:
CREATE OR REPLACE FUNCTION my_bool_to_str(f varchar2) RETURN VARCHAR2 IS b varchar2(2);BEGIN EXECUTE IMMEDIATE 'declare bl boolean; begin bl := ' || f || '; if bl then :1 := ''y''; else :1 := ''n''; end if; end;' using out b; return b;END;Then you can call it like this:
SELECT part_no, my_bool_to_str('stock_pkg.is_in_stock('|| part_no|| ')') in_stockFROM parts_tableThe difference from your wrapper is that it gets a varchar as input and not a boolean which the SQL engine doesn't recognize