I'm writing program in C which writes _FILENAME_ to mysql database. so I got variable (char) 'filename': "\\server\directory\file'name'.mp3" char *query; sprintf (&query, "INSERT INTO db (file) VALUES ('%s')", filename); ... Then mysql is executing this query, it returns syntax error, becouse query have " ' " character. OR in mysql it appears as: "\serverdirectoryfilename.mp3" Mysql ', \ symbols reads as control ...