GetProperties( ) (all attributes) for BLOBs

Question

Hello,
I am using Oracle 11g R2 SOE.
I am trying to practice this example that is similar to the one in the doc about :
getProperties( ) (all attributes) for BLOBsBut nothing gets updated in my table, even though it tells on the output 1 row is updated (as you can see below)
if I change the statement into Insert, it works perfectly.
What could be the reason ????
DECLARE
  img_data              BLOB;
  img_attrib        CLOB;
  mimeType          VARCHAR2(4000);
  width             NUMBER;
  height            NUMBER;
  fileFormat        VARCHAR2(32);
  contentFormat     VARCHAR2(4000);
  compressionFormat VARCHAR2(4000);
  contentLength     NUMBER;
BEGIN
   SELECT content, attrib, mimtype, width, height, fileformat, contentformat,
     compressionformat, contentlength INTO img_data, img_attrib, mimeType, width,
     height, fileFormat, contentFormat, compressionFormat, contentLength
     FROM com_photos WHERE id = 1012 FOR UPDATE;
  ORDSYS.ORDImage.getProperties(img_data, img_attrib,
         mimeType, width, height, fileFormat,
         contentFormat, compressionFormat, contentLength);
   DBMS_OUTPUT.put_line('Size of XML Annotations ' ||
                   TO_CHAR(DBMS_LOB.GETLENGTH(img_attrib)));
   DBMS_OUTPUT.put_line('mimeType: ' || mimeType );
   DBMS_OUTPUT.put_line('width: ' || width );
   DBMS_OUTPUT.put_line('height: ' || height );
   DBMS_OUTPUT.put_line('fileFormat: ' || fileFormat );
   DBMS_OUTPUT.put_line('contentFormat: ' || contentFormat );
   DBMS_OUTPUT.put_line('compressionFormat: ' || compressionFormat );
   DBMS_OUTPUT.put_line('contentLength: ' || contentLength );
   UPDATE com_photos SET
       content=img_data,
       attrib=img_attrib,
       mimtype=mimeType,
       width=width,
       height=height,
       fileformat=fileFormat,
       contentformat=contentFormat,
       compressionformat=compressionFormat,
       contentlength=contentLength
    WHERE id = 1012;
   COMMIT;
EXCEPTION
   WHEN OTHERS THEN
   RAISE;
END;and I get this result
Size of XML Annotations
mimeType: image/jpeg
width: 800
height: 500
fileFormat: JFIF
contentFormat: 24BITRGB
compressionFormat: JPEG
contentLength: 55966
1 row(s) updated.Another point, I am interested in getting only the width and the height of the image, but as I got i have to feed ORDSYS.ORDImage.getProperties with all parameters. Is there a way to get around ?
Best regards,
Fateh

Answer 1

I think you don't need the SELECT for ... UPDATE statement since you are not updating the BLOB. In the UPDATE statement there is no need to update the BLOB since you have not changed the BLOB at all, you are just reading the properties embedded in the image using getProperties.
However, I can't see anything obviously wrong.
You could drop the SELECT for ...UPDATE statement, which you is a good thing anyway.