Search notes:

ORA-06575: Package or function … is in an invalid state

create table tq84_tab (num number);
insert into tq84_tab values(42);

create or replace function tq84_fnc return number as
   ret number;
begin
   select max(num) into ret from tq84_tab;
   return ret;
end tq84_fnc;
/

drop table tq84_tab;

Error not yet recognized:

select * from user_errors where name = 'TQ84_FNC';

Only by executing the following select statement, Oracle realizes that the function has become invalid and throws ORA-06575: Package or function TQ84_FNC is in an invalid state.

select tq84_fnc from dual;

Because tq84_fnc was recompiled to be used in the select statement, an error is now recored in user_errors:

select text from user_errors where name = 'TQ84_FNC';
--
-- PL/SQL: ORA-00942: table or view does not exist
-- PL/SQL: SQL Statement ignored
--

Cleaning up

drop table tq84_tab;
drop function tq84_fnc;

ORA-06575: Package or function … is in an invalid state

See also