public class songs {
    int song_id ;
    String name_ref;
    String name ;
    String song_ref ;
    String song;
    public songs(String nr,String n,String sr, String s){
        name_ref=nr;
        name=n ;
        song_ref=sr ;
        song=s;
//      song_id=someDBcalculation(name_ref,name,song_ref,song);
    }
}

CREATE TABLE songs(
song_id int NOT NULL AUTO_INCREMENT,
name_ref varchar(255) NOT NULL UNIQUE,
name varchar(255) NOT NULL UNIQUE,
song_ref varchar(255) NOT NULL UNIQUE,
song varchar(255) NOT NULL UNIQUE,
PRIMARY KEY (song_id) 
);
insert into songs  (name_ref,name,song_ref,song) 
                values ("Haddocks' Eyes.","The Aged Aged Man.","Ways And Means","A-sitting On A Gate");