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 -----
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.