On Wed, 20 Sep 2006, jeremy0505_at_gmail.com wrote:
> In article <uac4v4aks.fsf_at_rcn.com>, Galen Boyer says...
>> On Tue, 19 Sep 2006, jeremy0505_at_gmail.com wrote:
>> > In article <ulkog4a9w.fsf_at_rcn.com>, Galen Boyer says...
>> >> On Mon, 18 Sep 2006, jeremy0505_at_gmail.com wrote:
>> >> > In article <uejua5rr0.fsf_at_rcn.com>, Galen Boyer says...
>> >> >
>> >> >> Why do you need to worry about redo?
>> >> >>
>> >> >>
>> >> > Perhaps I don't - see other responses.
>> >>
>> >> I would look at materialized views myself, because, that is really
>> >> what you are describing (ie, I want to have a query not have to
>> >> execute everytime, but instead, have it stored so I can get the
>> >> results quicker) An MV helps solve that in a most impressive
>> >> fashion.
>> >>
>> > This may help actually, yes - however when the user requests the
>> > data to be refreshed, it needs to be up-to-date rather than based
>> > on the latest snapshot (am I right that MVs are periodically
>> > refreshed rather than instantaneously with each transaction that
>> > may affect the content?).
>>
>>
>> Well, if you are worried about that, you certainly shouldn't be
>> trying to save your own manufactured snapshot. You will never get
>> that correct while Oracle will always get that correct.
>>
> It isn't a "own manufactured snapshot" - merely the results of a query
> such as "show me the orders in the last 24 hours" which we then are
> allowing the user to view in the way he chooses via the web interface.
> Every time the query runs, it will be on the current at the time data.
But, then, when the user subsequently looks at the data, it is not in
real-time. It, instead, is at some time after the "snapshot" was
taken. How come they are okay with the subsequent reads of the data,
but are not okay with the data maybe, already, being a little behind
exact committed transactions at the time of the initial query?
--
Galen Boyer
Received on Wed Sep 20 2006 - 22:01:04 CDT
