oracle性能优化

declare
type rid_Array is table of rowid index by binary_integer;
v_rid rid_Array;
v_Count PLS_INTEGER := 0;
v_Cur sys_refcursor;
v_SQL varchar2(2000) := ‘select t.rowid from calendar_info t where specialtype = 1 and title not like ‘‘%生日‘‘‘;
begin
open v_Cur for v_SQL;
loop
fetch v_Cur bulk collect
into v_rid limit 1000;
forall i in 1 .. v_rid.count()
update calendar_info set title =title||‘生日‘ where rowid = v_rid(i);
v_Count := v_Count + sql%rowcount;
commit;
exit when v_Cur%notfound;
end loop;
commit;
close v_Cur;
dbms_output.put_line(v_Count);
exception
when others then
rollback;
end;