Image retrieval error

Question

Hi,
I have a weird problem. I have a blob field in two tables. Both contain a potential thumbnail of a given document which is stored in a different table. I have a simple web application that displays the thumbnails using the PL/SQL web cartridge.
Here is the problem. In one environment (A HP 64 machine) the procedure works fine, it loads which ever image is required with no problems. The other environment that I am running is identical and runs on windows 2000 pro. In this environment one table allows me to show the thumbnails, the other does not...I have placed checks in the code to see whether the BLOB is being retrieved correctly for the thumbnail that is not showing; and it is definitely there.
Has anyone seen anything like this before ?
Here is a copy of the procedure,
PROCEDURE download_thumbnail(
pn_item_id IN number
) IS
CURSOR c_items ( id IN NUMBER ) IS
SELECT *
FROM bvhe_portal.bvhe_items
WHERE 1=1
AND item_id = id;
r_curr_item c_items%ROWTYPE; -- current item
lv_filename VARCHAR2(128) := 'thumb.gif';
lblob_dummy blob;
lv_dummymime VARCHAR2(128);
     lv_desc VARCHAR2(128);
BEGIN
OPEN c_items(pn_item_id);
FETCH c_items INTO r_curr_item;
IF c_items%FOUND THEN
IF (dbms_lob.getlength(r_curr_item.thumbnail) != 0) THEN
owa_util.mime_header('image/gif', FALSE);
htp.p('Content-Length: ' || dbms_lob.getlength(r_curr_item.thumbnail));
IF (instr(r_curr_item.file_name,'.',-1,1) != 0) THEN
lv_filename := substr(r_curr_item.file_name,1,instr(r_curr_item.file_name,'.',-1,1)-1)||'_thumb.gif';
END IF;
htp.p('Content-Disposition: inline; filename="'||lv_filename||'"');
owa_util.http_header_close;
wpg_docload.download_file(r_curr_item.thumbnail);
ELSE
-- start of thumbnail section
-- This section does not return an image ??????
SELECT thumbnail, mime_type, description
INTO lblob_dummy, lv_dummymime, lv_desc
FROM bvhe_portal.bvhe_item_types
WHERE 1=1
AND item_type_id = r_curr_item.item_type_id;
     owa_util.mime_header('image/gif', FALSE);
htp.p('Content-Length: ' || dbms_lob.getlength(lblob_dummy));
--htp.p('Content-Disposition: inline; filename="'||lv_desc || '_' || lv_filename||'"');
owa_util.http_header_close;
wpg_docload.download_file(lblob_dummy);
END IF;
ELSE
null;
--htp.p('Item could not be located.');
END IF;
CLOSE c_items;
END;
If anyone could help I would be most appreciative,
Thanks,
Mark

Answer 1

Hmmmm,
From a 10 minute look over, I can't see anything wrong. If your data was in an interMedia data type, you would be able to do a "checkProperties" to see if the image data was correct.
You might want to ask this question in the Oracle Portal forum that sopports the htp and owa packages.
Larry