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From Kristian Waagan <Kristian.Waa...@Sun.COM>
Subject Re: Perfroamnce of IN ( ... list ... ) statements
Date Mon, 06 Oct 2008 09:22:40 GMT
On 06.10.08 10:53, Tim Dudgeon wrote:
> Peter Ondruška wrote:
>> What Derby version is it?
>> How does it perform if you re-create index on foo_id column?
> 
> The column in the primary key column, so has an index.

Hello Tim,

It would be helpful to know if compressing the table helps (or 
re-creating the index). The idea is to update the statistics used by the 
optimizer.

I saw the question in an earlier post, but no reply. Which version of 
Derby are you using?


regards,
-- 
Kristian

> 
> Tim
> 
>>
>> p.
>> On Sun, Oct 5, 2008 at 10:07 PM, Tim Dudgeon 
>> <tdudgeon@informaticsmatters.com 
>> <mailto:tdudgeon@informaticsmatters.com>> wrote:
>>
>>     If I run a statement like this is Derby:
>>     SELECT COL1, COL2 FROM FOO WHERE FOO_ID IN ( 1, 31, ..... 4567)
>>     it seems unexpectedly slow. Its actually faster to retrieve each row
>>     individually using a for loop that it is to use the IN ( ..  list
>>     ... ) clause. This seems strange.
>>
>>     Thanks
>>
>>     Tim
>>
>>
> 


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