On 12 Jul 2005 03:23:56 -0700, "hopehope_123" <hopehope_123_at_yahoo.com>
wrote:
>Hi Sybrand ,
>
>Thanks for your mail. You are right that this is a strange question .
>I am asking this question just to know how fast two tables can be
>joined. As you say , for every individual row of the driving table ,
>the nondriving table need to be looked up , but i want to know how fast
>this can be done .( Or can it be done by using better io rate) ( I
>dont mean hash join or nested loop join , i am checking the os part .)
>
>Hope this time this is little bit detailed.
>Regards,
>hope
Still doesn't make sense. Too many factors come into play. Above all
you are querying the detail table (for nothing) over and over and over
again. Assuming your physical I/O (at the Oracle level) is high (and
obviously you didn't investigate this), you will be reading the same
disk blocks over and over and over again, and you will suffer from
disk latency. But then you are conducting an useless experiment to
demonstrate how you can screw up a database, so who cares?
--
Sybrand Bakker, Senior Oracle DBA
Received on Tue Jul 12 2005 - 13:13:48 CDT
