JohnSilver182
BANNED | Редактировать | Профиль | Сообщение | Цитировать | Сообщить модератору
Юзаю сабж давно но удивляюсь его дикому оптимизатору
Код: select * from aptdrugpresent
where scode in (10432) |
Цитата:
Plan
PLAN (APTDRUGPRESENT INDEX (ADP_ADP))
------ Performance info ------
Prepare time = 0ms
Execute time = 31ms
Avg fetch time = 2,58 ms
Current memory = 9 449 016
Max memory = 10 252 776
Memory buffers = 2 048
Reads from disk to cache = 9
Writes from cache to disk = 0
Fetches from cache = 1 884 |
Далее , подзапрос возвращает ОДНО значение , Но ТОРМОЗА !!
Код:
select * from aptdrugpresent
where scode in (select ap.apt_code from apt_priv ap ) |
Цитата: Plan
PLAN (AP INDEX (PK_APT_PRIV))
PLAN (APTDRUGPRESENT NATURAL)
Adapted Plan
PLAN (AP INDEX (PK_APT_PRIV)) PLAN (APTDRUGPRESENT NATURAL)
------ Performance info ------
Prepare time = 0ms
Execute time = 5s 422ms
Avg fetch time = 451,83 ms
Current memory = 9 445 924
Max memory = 10 252 776
Memory buffers = 2 048
Reads from disk to cache = 21 459
Writes from cache to disk = 586
Fetches from cache = 4 490 886 |
|
