Nhibernate笔记
/// <summary> /// one to many ,IQueryOver中如何使用预加载(一次加载全部关联的) /// </summary> /// <param name="customerId"></param> /// <returns></returns> public IList<Customer> GetCustomersById(int customerId) { var p = _session.QueryOver<Customer>() .WhereRestrictionOn(c => c.FirstName).IsLike("ly%") .Fetch(c => c.Orders).Eager .List<Customer>(); return p; } [TestMethod] public void TestMethodCustomer() { var c = dProvider.GetCustomersById(1); /* * 预加载由于其生成的SQL语句包括了Join或子查询语句,因此它无法保证获取到集合中元素的唯一性,例如:A包含两个子元素B和C,那么通过预加载后, * 第一级查询取出的列表中会包括两个A对象,而不是通常我们想象的一个。所以,启用预加载后获取到的列表,需要手动的解决唯一性的问题, * 最简单的就是把列表装入ISet里“过滤”一次。 */ var customer = new HashSet<Customer>(c).ToList(); int count = customer.Count; foreach (var cu in customer) { foreach(Order od in cu.Orders) { var o = od.OrderDate; } } //Assert.AreEqual(1, c.CustomerId); }
/// <summary> /// 批量 --用ISessionFactory先打开OpenStatelessSession,再用session.Insert(item); /// </summary> /// <param name="list"></param> public void BatchingData(List<Customer> list) { using(var session = Sessions.Factory.OpenStatelessSession()) using (var tx = session.BeginTransaction()) { foreach (var item in list) { session.Insert(item); } tx.Commit(); } }
/// <summary> /// 分页 /// </summary> /// <param name="pageIndex"></param> /// <param name="pageSize"></param> /// <returns></returns> public IList<Customer> GetListPage(int pageIndex, int pageSize) { using (var session = Sessions.GetSession()) using (var tx = session.BeginTransaction()) { var p = session.QueryOver<Customer>() .OrderBy(c => c.CustomerId).Asc .Skip((pageIndex - 1) * pageSize) .Take(pageSize) .List(); return p; } }
public class Sessions { private static readonly object lockObj = new object(); private static ISessionFactory _factory; static Sessions() { } /// <summary> /// 这是一个典型的double lock方式,用来产生线程安全的Singletion(单例)对象。 /// </summary> public static ISessionFactory Factory { get { if (_factory == null) { lock (lockObj) { if (_factory == null) { NHibernate.Cfg.Configuration cfg = new NHibernate.Cfg.Configuration().Configure(); //cfg.AddAssembly(Assembly.GetExecutingAssembly()); _factory = cfg.BuildSessionFactory(); } } // end lock } return _factory; } } public static ISession GetSession() { return Factory.OpenSession(); } }
/// <summary> /// 2个like的or查询 /// </summary> /// <param name="fristName"></param> /// <param name="lastName"></param> /// <returns></returns> public static IList<Customer> GetListByWhere(string fristName, string lastName) { using (var session = Sessions.GetSession()) using (var tx = session.BeginTransaction()) { var customer = session.QueryOver<Customer>() .Where(Restrictions.On<Customer>(c => c.FirstName).IsLike("%" + fristName + "%") || Restrictions.On<Customer>(s => s.LastName).IsLike("%" + lastName + "%")) .List(); return customer; } }
其他条件的or查询
.Add(Restrictions.Or( Restrictions.Where<Cat>(c => c.Age > 5) Restrictions.On<Cat>(c => c.Name).IsIn(new string[] { "Max", "Paddy" })))
用对方法才有效率,做对事情才有效果
“麻烦”是自己“处理”不当的结果
“困难”是自己“学习”不够的反射
“挫折”是自己“努力”不足的代价
“麻烦”是自己“处理”不当的结果
“困难”是自己“学习”不够的反射
“挫折”是自己“努力”不足的代价