I need to be able to save the data from a BLOB column to an external file on the server, preferably in a temporary directory. Afterwards I will add a header to the file and send to the web client. I believe I know how to add the header. However, everything I have read in DBMS_LOB or UTIL_FILE describes saving a BFILE or CLOB to a BLOB, but not the reverse. Can you save from a BLOB to an external file on the server? The processing must be done on the Server.
I have been able to select TEXT from a VARCHAR column and save to a file on the server but unable to select a BLOB and save to the file.
UTL_FILE would be the correct thing to use, but I seem to recall that it didn't work for binary files. It apparently adds CR LF data into the files when written. I am not sure if this has changed recently or not. You might try posting in the database or PL/SQL forum about UTL_FILE.