The difference between Hibernate's Save method and SQL insert

public Boolean Adddiscuss (discuss discuss) {
Session session = Hibernatesessionfactory.getsession ();//Get Session Object
try {
Session.save (Discuss);//save information, non-line error,cannot add or update a child row:a FOREIGN KEY constraint fails

} catch (Exception ex) {
Ex.printstacktrace ();
return false;
//}
Hibernatesessionfactory.closesession ();//Close Session Object
return true;
Session session = Hibernatesessionfactory.getsession ();
Query query = session.createsqlquery ("INSERT into discuss values (0,?,?,?,?,?,?)");
Query.setparameter (0, Discuss.gettid ());
Query.setparameter (1, Discuss.getuid ());
Query.setparameter (2, Discuss.getcontent ());
Query.setparameter (3, Discuss.gettime ());
Query.setparameter (4, Discuss.gettheme ());
Query.setparameter (5, Discuss.getname ());
System.out.println (query);
int num=query.executeupdate ();

Hibernatesessionfactory.closesession ();
if (num>0)
return true;
else{
return false;
}
}

The difference between Hibernate's Save method and SQL insert