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From Edson Carlos Ericksson Richter <edson.rich...@mgrinformatica.com.br>
Subject Re: Server side cursor
Date Thu, 02 Jun 2005 18:10:10 GMT
Yes, that's what I have in mind.

See, if I issue a very large, expensive select * from huge_table, if I 
have server side cursors, response is immediate, because there is 
nothing to process. My cursor is just a pointer to real data in the table.

Even if I make a select * from huge_table order by some_column, if the 
column is indexed, the server-side cursor is just a pointer to index... 
And real action goes when I scroll records...

Thanks for clarification.

Richter


Satheesh Bandaram escreveu:

> Thinking about this some more, may be you mean SQL cursors by 
> "server-side cursors". These are definitely not supported by Derby. 
> Derby only has JDBC based cursors. SQL cursors didn't leap to my head, 
> since Derby doesn't have them.
>
> Satheesh
>
> Satheesh Bandaram wrote:
>
>>By "server-side cursors", do you mean the ability to process on the
>>server, using procedures/functions? Same cursor mechanism works on the
>>server too. See if 'Derby server-side programming' part in developer
>>guide provides more info:
>>
>>http://incubator.apache.org/derby/docs/devguide/cdevspecial.html
>>
>>Satheesh
>>
>>Edson Carlos Ericksson Richter wrote:
>>
>>  
>>
>>>Thanks.
>>>
>>>I made a fgrep -iR "server side" * in docs and found nothing about it.
>>>a fgrep -iR "cursor" * found several docs, but none specific about
>>>server side cursors.
>>>
>>>Even a fgrep -iR "cursor" | egrep -i "server" reveal no doc about
>>>server side cursor.
>>>
>>>May be the terminoly I'm looking for is wrong. Under what name server
>>>side cursor subject could be find?
>>>
>>>Thanks again,
>>>
>>>Edson Richter
>>>
>>>
>>>
>>>Satheesh Bandaram escreveu:
>>>
>>>    
>>>
>>>>Derby certainly can. Data for cursors in Derby is fetched on demand.
>>>>Check Derby documentation for more info.
>>>>
>>>>Satheesh
>>>>
>>>>Edson Carlos Ericksson Richter wrote:
>>>>
>>>> 
>>>>
>>>>      
>>>>
>>>>>Is derby able to delivery very large resultsets (really bigger than
>>>>>phisical memory of the db server) throught server side cursors?
>>>>>
>>>>>Thanks,
>>>>>
>>>>>  
>>>>>        
>>>>>
>>>>
>>>> 
>>>>
>>>>      
>>>>
>>>    
>>>
>>
>>  
>>


-- 
Edson Carlos Ericksson Richter
MGR Informática Ltda.
Fones: 3347-0446 / 9259-2993


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