                             expire     : if ttl then expire_time(ttl)
                         cb     : cb
                 else
-                    # blob already in the DB, so see if we need to change the expire time
+                    dbg("blob already in the DB, so see if we need to change the expire time")
                     @_extend_blob_ttl
                         expire : rows[0].expire
                         ttl    : opts.ttl

                        rows = x.rows; cb(err)
            (cb) =>
                if rows.length == 0 and opts.compress
                    # compression requested and blob not already saved, so we compress blob
                    switch opts.compress
                        when 'gzip'
                            zlib.gzip opts.blob, {level:opts.level}, (err, blob) =>

            if uuid != opts.uuid
                opts.cb("the sha1 uuid (='#{uuid}') of the blob must equal the given uuid (='#{opts.uuid}')")
                return
        dbg = @_dbg("save_blob(uuid='#{opts.uuid}')")
        dbg()
        rows = ttl = undefined
        async.series([
            (cb) =>
