Nasıl dosyaya DB ikili veri ayıklamak

CREATE TABLE `mail_attachs` (
  `attachid` int(15) NOT NULL auto_increment,
  `filecontent` longtext,
  PRIMARY KEY  (`attachid`),
) ENGINE=MyISAM 

The binary data has been saved in the filecontent column. I want to extract the files and text saved in this column and save it to a file on the same server. The filename will contain the attachid so that I can identify and relate the record found in the DB.