Session.delete() not working

Question

I am trying to delete ROW in SQL DB by session.delete() on calling a RemoveProject Servlet where getting Parameters for which I want to delete Object from db.

SessionFactory sf=DataConnect.getConnect();
    Session sess=sf.openSession();
    Transaction tr=sess.beginTransaction();
    try{
    Query qur=sess.createQuery("from Project");
    org.hibernate.Criteria cr=sess.createCriteria(Project.class);
    //cr.add(Restrictions.eq("name",request.getParameter("name")));
    cr.add(Restrictions.idEq(Integer.parseInt(request.getParameter("id"))));
                        List obj=cr.list();

     for (Iterator iterator = obj.iterator(); iterator.hasNext();)
     {
        osl.pojo.Project devobj = (osl.pojo.Project) iterator.next(); 
         System.out.print("DELETING"+devobj.getName()+"from Project");
        sess.delete(devobj);



        tr.commit();System.out.println("ROW DELETED");
     }

    }catch(HibernateException he){ he.printStackTrace(); ;tr.rollback(); response.sendRedirect(request.getRequestURI());}

But it is not working I also Tried Flushing Session.

I am getting this Message in Glassfish Console.

***Info:   DELETING DATA_To_BE_DELETED from Project

WARN:   SQL Error: 1064, SQLState: 42000

ERROR:   You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'index=1' at line 1

Info:   HHH000010: On release of batch it still contained JDBC statements
Severe:   org.hibernate.exception.SQLGrammarException: could not execute statement***

Answer 1

The problem is because you are trying commit inside the for loop, so change it to outside the loop:

for (Iterator iterator = obj.iterator(); iterator.hasNext();) {
    osl.pojo.Project devobj = (osl.pojo.Project) iterator.next(); 
    System.out.print("DELETING"+devobj.getName()+"from Project");
    sess.delete(devobj);
}
tr.commit();

Answer 2

所述问题的数据库列名称与数据库属性“索引”冲突，因此在将对象数据更新回Sql时出错，并且在SQL语法中导致错误。