Nhibernate:为什么会话缓存和查询结果不匹配?

我们正在使用Nhibernate v4.0.30319,我们正在使用 Flushmode.Commit 让我们考虑一个例子 Employee 桌子与 IsActive DB中的列。

在其中一笔交易中,我们正在获取 员工 具有 empId = 100 如下所示:

var employee = session.Get<Employee>(100);

employee.IsActive = false;

它还没有被承诺,甚至还没有被刷新。

我们立即运行查询以获取所有活动的员工。

var activeEmployees = session.CreateCriteria<Employee>()
                             .Add(Restrictions.Eq("IsActive", true))
                             .List<Employee>();

现在在 activeEmployees 结果我仍然得到empId=1的员工详细信息,但 IsActive 价值为 false .

我无法理解为什么这种不一致的行为。如果查询在数据库上运行,那么它应该返回empId-100 IsActive 值“True”,否则如果它在一级缓存上运行,则不应在查询结果中包含empId-100。在这里,它将返回EmpId-1 IsActive 错误的

它为什么会这样?我已经阅读了一些文章和配置细节,但我无法弄清楚这种行为。

我创建了一个控制台应用程序:

员工表:

Nhibernate配置:

 if (_sessionFactory == null)
 {
     var configuration = new Configuration();

     // Set connection properties for SQL Server
     configuration.SetProperty(NHibernate.Cfg.Environment.ConnectionDriver, typeof(SqlClientDriver).AssemblyQualifiedName);
     configuration.SetProperty(NHibernate.Cfg.Environment.ConnectionString, "Data Source=INLT-D72FCSG3\\SQLEXPRESS;Initial Catalog=TestDB;Integrated Security=True;");
     configuration.SetProperty(NHibernate.Cfg.Environment.Dialect, typeof(MsSql2012Dialect).AssemblyQualifiedName);
     configuration.SetProperty(NHibernate.Cfg.Environment.ShowSql, "true");
     configuration.SetProperty(NHibernate.Cfg.Environment.FormatSql, "true");
     configuration.SetProperty(NHibernate.Cfg.Environment.Hbm2ddlAuto, "update");


     configuration.AddFile("Employee.hbm.xml"); // Add your mapping files
     _sessionFactory = configuration.BuildSessionFactory();
 }
 return _sessionFactory;

执行:

 using (var session = NHibernateHelper.OpenSession())
 {
     session.FlushMode = FlushMode.Commit;
     // Start a new transaction
     using (var transaction = session.BeginTransaction())
     {
         // Load employee with Id = 100
         var employee = session.Get<Employee>(1);
         Console.WriteLine($"Before Update: {employee.Name} - IsActive: {employee.IsActive}");
     // Modify the IsActive field to false (this marks the entity as dirty)
     employee.IsActive = false;

     // The entity is now in the session cache with IsActive = false
     Console.WriteLine($"After Update: {employee.Name} - IsActive: {employee.IsActive}");

     // Now, we fetch active employees (IsActive = true)
     var activeEmployees = session.CreateCriteria<Employee>()
                                  .Add(Restrictions.Eq("IsActive", true))
                                  .List<Employee>();

     // Print the active employees (it should still return the modified entity in the session cache)
     Console.WriteLine("\nActive Employees (before commit):");
     foreach (var emp in activeEmployees)
     {
         Console.WriteLine($"{emp.Name} - IsActive: {emp.IsActive}");
     }

     // Commit the transaction to persist changes to the database
     transaction.Commit();
 }

}

  // Simulate a new session for the next query (to see changes after commit)
 using (var session = NHibernateHelper.OpenSession())
 {
     var activeEmployees = session.CreateCriteria<Employee>()
                                  .Add(Restrictions.Eq("IsActive", true))
                                  .List<Employee>();

     // Print the active employees after the session is committed
     Console.WriteLine("\nActive Employees (after commit):");
     foreach (var emp in activeEmployees)
     {
         Console.WriteLine($"{emp.Name} - IsActive: {emp.IsActive}");
     }
 }

输出:

NHibernate:
    SELECT
        employee0_.Id as id1_0_0_,
        employee0_.Name as name2_0_0_,
        employee0_.IsActive as isactive3_0_0_
    FROM
        Employee employee0_
    WHERE
        employee0_.Id=@p0;
    @p0 = 1 [Type: Int32 (0:0:0)]
Before Update: John Doe - IsActive: True
After Update: John Doe - IsActive: False
NHibernate:
    SELECT
        this_.Id as id1_0_0_,
        this_.Name as name2_0_0_,
        this_.IsActive as isactive3_0_0_
    FROM
        Employee this_
    WHERE
        this_.IsActive = @p0;
    @p0 = True [Type: Boolean (0:0:0)]

Active Employees (before commit):
John Doe - IsActive: False
Jane Smith - IsActive: True
Bob Brown - IsActive: True
Alice Green - IsActive: True
NHibernate:
    SELECT
        this_.Id as id1_0_0_,
        this_.Name as name2_0_0_,
        this_.IsActive as isactive3_0_0_
    FROM
        Employee this_
    WHERE
        this_.IsActive = @p0;
    @p0 = True [Type: Boolean (0:0:0)]

Active Employees (after commit):
Jane Smith - IsActive: True
Bob Brown - IsActive: True
Alice Green - IsActive: True

谢谢,

纳盖斯雷。