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From "Raymond Kroeker" <raym...@thinkparity.com>
Subject Re: Query on a blob table
Date Tue, 24 Jul 2007 15:52:49 GMT
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.

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