create or replace type acc_type as object
(acc varchar2(50))
/

create or replace type acc_table as table of acc_type
/

create or replace function str2table (acc_str in varchar2) return acc_table pipelined
is
v_str varchar2(30000) := acc_str;
v_acc varchar2(30);
v_acc_end pls_integer;
begin
loop
v_acc_end := instrb(v_str,',');
exit when (v_acc_end=0 or v_str is null);
v_acc := substrb(v_str,1,v_acc_end-1);
v_str := ltrim(v_str,v_acc);
v_str := ltrim(v_str,',');
pipe row(acc_type(rtrim(v_acc,';')));
end loop;
return;
end;
/