you have to be a bit careful!!.
if it's in a clob and you are on oracle and your NLS language is set
incorrectly , your database will translate the content of it's clobs to a
different codepage, which might include conversion from single byte to
multibyte character sets.

sometimes ,  i might want to have chinese characters on my oracle database, i
generally write them to a blob , so that the database does not tanslate and
interpret them as single byte, instead of multibyte.

that said:
this is the code to get a blob , the "photo" is stored in the content field
of the database.
just modify the  "bo" to a file stream

   public static byte[] getPhoto(long photoId) throws Exception {
 static final int MAXBUFSIZE = 4096;
       Section section = null;
       PreparedStatement st = null;
       ResultSet rset = null;

       try {
           String sql =
               "Select content from photo_store where deleted=0 and
id=?";
           st = c.prepareStatement(sql);
           st.setLong(1, photoId); // Bind the photo id

           ////Oracle
           rset = st.executeQuery(); // Execute Query

           oracle.sql.BLOB blob = null;

           if (rset.next()) /*this is always true*/ {
               blob = (oracle.sql.BLOB) rset.getObject(1);
           }

           if (blob != null) {
               BufferedInputStream bis =
                   new BufferedInputStream(blob.getBinaryStream());
               ByteArrayOutputStream bo = new ByteArrayOutputStream();
               byte[] buf = new byte[MAXBUFSIZE];
               int n = 0;

               while ((n = bis.read(buf, 0, MAXBUFSIZE)) != -1) {
                   bo.write(buf, 0, n);
               }

               bo.flush();
               bo.close();
               bis.close();

               buf = null;

               return bo.toByteArray();
           }
       } catch (Exception ex) {
           Error_stuff.handleError(ex, -1, -1);

           // ex.printStackTrace();
       } finally {
           if (st != null) {
               try {
                   st.close();
               } catch (Exception ex1) {
                   Error_stuff.handleError(ex1, -1, -1);
               }
           }
       }

       return null;
   }