Keep the result set open, retieve from the set as necessary, probably
using a cursor. That way if someone is doing a search that has 1 million
records and after I display the first 10 and the client chooses the 3rd
one, we have only created 10 objects.
Oleg Nitz wrote:
> Dave Smith wrote:
>
>>Close, but what if my initial list is 1 million records. That means that
>>you still have to load and create 1 million pk's. I think you need to
>>define the query and return the list. When the Collection asks for the
>>next record or record # 10 then you not only need to load the record but
>>also the pk.
>>
> Sorry, I don't understand your idea.
> Do you propose to keep the ResultSet open?
> Do you mean using SQL extensions like LIMIT clause?
>
> Oleg
>
>
>>Oleg Nitz wrote:
>>
>
>>>Hi,
>>>
>>>Yes, I am working on this. Here is the algorithm. The list of PK
>>>values are loaded at first and stored to LRU cache of query results on
>>>server, the id of the list is passed to client. When client requests
>>>some CMP field, the list id and index in the list of the given entity
>>>is passed to server. Next N entities are loaded from DB (SQL statement
>>>has the form "SELECT ... WHERE pk=? OR pk=? ...") and returned to
>>>client. When client requests the same CMP field for next N entities,
>>>no interaction with with server is done to serve this request.
>>>
>>>Oleg
>>>
>>>Peter Fagerlund wrote:
>>>
>>>
>>>>on 1-09-24 05.36, Dain Sundstrom at [EMAIL PROTECTED] wrote:
>>>>
>>>>
>>>>>Maybe I am stupid, but I have have no idea what this means.
>>>>>
>>>>>
>>>>I do not think so ! ... it is me being unclear -perhaps ... -this means, A
>>>>pattern is great, and especially so, if there is a good implementation
>>>>"template" I can use, and customise for my application ...
>>>>
>>>>
>>>>A page_by_page_iterator should have an idee of the amount of records it is
>>>>capeble to display for its user -say 100.000.000 -when a user request a list
>>>>s/he should get a list of some -then perhaps the implementation prefetch
>>>>some more data in close perimeter to where in the index the user is
>>>>navigating ...
>>>>
>>>>
>>>>-get metadata
>>>> -fetch some data to list
>>>> - display the list
>>>> -prefetch some more
>>>>-wait for new input
>>>>
>>>>
>>>>Also a centralised cache for all users of the iterator -that can act
>>>>according to how static the data is ... would help ...
>>>>
>>>>
>>>>A page_by_page_iterator for really large datasets would work best in tandem
>>>>with a lighter db that has a prebuilt index ! ...
>>>>
>>>>
>>>>/peter_f
>>>>
>>>>
>>>
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>>>>
>>>
>>>
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>
>
>
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