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From dag.wan...@oracle.com (Dag H. Wanvik)
Subject Re: Performance problem with derby
Date Sat, 03 Sep 2011 01:50:37 GMT
mogoye <sylvain.roulet@eloquant.com> writes:

> Should I understand that is no way for me to optimize a request used to
> display few elements on a large result using pagination with derby 1.0.8 ?

If sorting is avoided by using the index, fewer rows would potentially
be fetched from the store using N ROWS ONLY, but the application could
also just stop reading more from the result set (modulo row
prefetching). Often using Derby's support for JDBC scrollable, (possibly
updatable) result sets may be an alternative way to page results.


> Dag H. Wanvik-2 wrote:
>> On 8/31/2011 7:19 PM, Mike Matrigali wrote:
>>> The OFFSET feature is relatively new to derby and I am not sure if the 
>>> optimizer has been fully updated to understand it.  Maybe someone who
>>> knows more about the OFFSET feature can comment if the optimizer has 
>>> been updated to know that this query is only going to look at 50 rows
>>> rather than all of them?
>> It hasn't been updated to understand this yet.
>> Dag

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