db-derby-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Michael Segel" <mse...@segel.com>
Subject RE: SELECT query takes 5 secs, what can I do?
Date Tue, 15 Sep 2009 12:21:50 GMT
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


Mime
View raw message