具有复合 ID 错误的标准

Question

NHibernate。 我有 3 个表：

Employee {PK:EmployeeId, Name, LastName, ...}

Project {PK: ProjectId, date, name, ...}

EmployeebyProject {< strong>PK:FK: EmployeeId, ProjectId, date, ...}

我需要做一些增删改查，此时我在 tabla EmployeebyProject 中有一些记录。所以我试图找人记录这些记录。这是使用条件的方法，但发生了以下错误：“GenericADOException，无法执行查询”“Column EmployeeId is not valid”，“Column ProductId is not valid”。 此条件的问题是无法转到 Employee 和 Project 表来查询 idEmployee 和 idProject。 那么我该怎么做呢？

 public EmployeebyProject GetEmployeebyProjectByIdEmployee(int idEmployee, int idProject)
        {
            using (ISession session = NHibernateSessionBuilder.OpenSession())
            {
                var employeebyProject = session
                        .CreateCriteria(typeof(EmployeebyProject))
                        .CreateCriteria("Employee", "Employee")
                        .Add(Restrictions.Eq("EmployeeId", idEmployee))
                        .UniqueResult<EmployeebyProject>();
                return employeebyProject;
            }
        }

这是 EmployeebyProject 的映射：

<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"
                   assembly="AdminProject"
                   namespace="AdminProject.Business.Entity">

  <class name="EmployeebyProject">

    <composite-id>
      <key-many-to-one name="Employee" column="EmployeeId"  class="Employee"></key-many-to-one>
      <key-many-to-one name="Project" column="ProjectId"  class="Project" ></key-many-to-one>
    </composite-id> 

    <property name="DateBegin" type="DateTime"/>
    <property name="DateEnd" type="DateTime"/>

  </class>

</hibernate-mapping>

Answer 1

您从 .Add(Restrictions.Eq("EmployeeId", idEmployee)) 调用的 EmployeeId 属性是错误的，EmployeeId 不属于 EmployeeProject 实体。它属于 Employee 实体。因此，您的查询应该重写为

    public EmployeebyProject GetEmployeebyProjectByIdEmployee(int idEmployee, int idProject)
    {
        using (ISession session = NHibernateSessionBuilder.OpenSession())
        {
            var employeebyProject = session
                    .CreateCriteria(typeof(EmployeebyProject))
                    .CreateCriteria("Employee", "EmployeeAl")
                    .CreateCriteria("Project", "ProjectAl")
                    .Add(Restrictions.Eq("EmployeeAl.id", idEmployee))
                    .Add(Restrictions.Eq("ProjectAl.id", idProject))
                    .UniqueResult<EmployeebyProject>();
            return employeebyProject;
        }
    }

，我认为您应该调用 .CreateAlias("Employee", "EmployeeAl") 而不是 .CreateCriteria("Employee", "EmployeeAl")代码> 和项目相同