How to unload blob from the database?

There is more than one post on how to unload blob from the database, mostly in plsql with utl_file.put_raw (see note 330146.1) and with java with FileOutputStream (see note 247546.1) Unfortunately both are terribly slow due to the 32k limitation of put_raw in utl_file and due to a low “optimum buffer size” retrieved by myBlob.getBufferSize(), […]