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From "dev@xx" <...@proxiflex.fr>
Subject Re: SELECT query takes 5 secs, what can I do?
Date Tue, 15 Sep 2009 12:37:11 GMT
>Can you 'detatch' your index? By this I mean store the index on a different 
>disk?

Is this possible with Derby ? I did look for this feature but didn't find a 
way to do it ...

I found that log could be set on different device but not index...

JY Linet

----- Original Message ----- 
From: "Michael Segel" <msegel@segel.com>
To: "'Derby Discussion'" <derby-user@db.apache.org>
Sent: Tuesday, September 15, 2009 2:21 PM
Subject: RE: SELECT query takes 5 secs, what can I do?


> This is also true.
>
> Can you 'detatch' your index? By this I mean store the index on a 
> different
> disk?
>
> Also what type/size machine are you running your query on? How much 
> memory?
> What else is in the table? Are the rows fat?
>
> HTH to point you down a possible decision path.
>
> -Mikey
>
>> -----Original Message-----
>> From: Brett Wooldridge [mailto:brett.wooldridge@gmail.com]
>> Sent: Tuesday, September 15, 2009 4:37 AM
>> To: Derby Discussion
>> Subject: Re: SELECT query takes 5 secs, what can I do?
>>
>> Consider making a separate archive table and live table.  Looking at
>> that query, I doubt any other index will help.
>>
>> Sent from my iPhone
>>
>> On Sep 15, 2009, at 17:07, Andrew Bruno <andrew.bruno@gmail.com> wrote:
>>
>> > Hello,
>> >
>> > I have a query that used to take 10secs to run, i.e.
>> >
>> > select * from Message m where
>> > m.m
>> > essageId='<7997716ED1AF3D47A35D74FA2CB610920255303F@somedomain.com>'
>> > and m.id != 933927 and m.archived=1
>> >
>> > The Message table has around one million rows.
>> >
>> > I added the following index
>> >
>> > CREATE INDEX IDX_Message_MessageId ON ExchangeSync.Message (messageId)
>> >
>> > and now it takes 5secs.
>> >
>> > Is there anything else I can do?
>> >
>> > Should I add an index on the boolean "archived" column too?
>> >
>> > Any performance hints appreciated.
>> >
>> > Thanks
>> > Andrew
>
> 


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