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From "Raymond Kroeker" <raym...@thinkparity.com>
Subject Re: Query on a blob table
Date Tue, 24 Jul 2007 16:12:35 GMT
Thanks Piet.  I changed the query to:

select CONTENT_SIZE from DOCUMENT_VERSION order by DOCUMENT_ID;

Then summed the values instead of using the aggregate.

On 7/24/07, Raymond Kroeker <raymond@thinkparity.com> wrote:
>
> I'm also using:
> Windows XP - Java 1.6.0_01
> Ubuntu Dapper Drake (6.06) - Java 1.6.0
>
>
>
> On 7/24/07, Raymond Kroeker < raymond@thinkparity.com> wrote:
> >
> > Sorry about that I'm using Derby 10.2.2.0.
> >
> > Raymond
> >
> > On 7/23/07, Piet Blok < pbhome@wanadoo.nl> wrote:
> > >
> > >  Raymond,
> > >
> > > Some time ago I encountered the same problem and reported it here in a
> > > thread "Strange performance issue with BLOB's". I also found a
> > > workaround for this problem:
> > >
> > > If this is your original query:
> > > select sum(CONTENT_SIZE) from DOCUMENT_VERSION;
> > > add a dummy WHERE clause like this:
> > > select sum(CONTENT_SIZE) from DOCUMENT_VERSION where DOCUMENT_ID > 0;
> > >
> > > (assuming ofcourse that DOCUMENT_ID is a positive number)
> > >
> > >
> > > Kind regards,
> > >
> > > Piet Blok
> > >
> > > ----- Original Message -----
> > >  *From:* Raymond Kroeker <raymond@thinkparity.com>
> > > *To:* derby-user@db.apache.org
> > > *Sent:* Tuesday, July 24, 2007 3:20 AM
> > > *Subject:* Query on a blob table
> > >
> > > Hi All,
> > >     I have a table encompassing blobs as such:
> > >
> > > CREATE TABLE DOCUMENT_VERSION
> > > (
> > >    DOCUMENT_ID BIGINT not null,
> > >    CONTENT BLOB not null,
> > >    CONTENT_SIZE BIGINT not null,
> > >    CONTENT_CHECKSUM VARCHAR(256) not null,
> > >    CHECKSUM_ALGORITHM VARCHAR(16) not null,
> > >    CONSTRAINT DOCUMENT_VERSION_PK PRIMARY KEY (DOCUMENT_ID)
> > > );
> > >
> > >
> > >   Now I've loaded 175 rows of 256B blobs and a single row containing a
> > > 250MB blob.  When I run the query
> > >
> > > select sum(CONTENT_SIZE) from DOCUMENT_VERSION;
> > >
> > >   it takes ~10s += 1.5s to complete.  Am I missing something?
> > >
> > >   I've tried indexing CONTENT_SIZE (after seeding the data) without
> > > any luck.
> > >
> > > --
> > >
> > > --------------------------------------------------------------------------------
> > > Raymond Kroeker
> > > thinkParity Solutions Inc.
> > >
> > >
> >
> >
> > --
> >
> > --------------------------------------------------------------------------------
> > Raymond Kroeker
> > thinkParity Solutions Inc.
> >
>
>
>
> --
>
> --------------------------------------------------------------------------------
> Raymond Kroeker
> thinkParity Solutions Inc.
>



-- 
--------------------------------------------------------------------------------
Raymond Kroeker
thinkParity Solutions Inc.

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