Oracle Designer - ORA-7445 when deleting an object from the Repository

Metalink Doc Id:578441.1

Workaround is:

alter system set "_optimizer_cost_based_transformation"=off scope=both;

or create on logon trigger for designer users to alter the session, for
example:
create or replace trigger .on_logon
after logon on database
begin
execute immediate 'alter session set
"_optimizer_cost_based_transformation"=off';
end;