Question

一周前我问how to propagate a parameter for joins in a ORM。建议的解决方案看起来很有希望 - 使用NHibernate过滤器。这就是我正在做的事情：

过滤类：

public class VersionFilter : FilterDefinition
{
    public static readonly string Name = typeof(VersionFilter).AssemblyQualifiedName;

    public static readonly string Parameter = "AsOf";

    private static readonly string SqlParameter = ":" + Parameter;
    private static readonly string Condition
        = " ISNULL(" + SqlParameter + ") AND ( ISNULL(ValidTo) )" +
          " OR ( ValidFrom < " + SqlParameter + " AND " + SqlParameter + "  <= ValidTo )"
    ;
    private static readonly IDictionary<string, IType> ParameterTypes = 
        new Dictionary<string, IType>
        {
            {Parameter, NHibernateUtil.Int64}
        }
    ;

    public VersionFilter(): base(Name, Condition, ParameterTypes, true)
    {
    }
}

在Main：

public class Program
{
    static void Main(string[] args)
    {
        log.Info("VersionedDataModel1.Program::start");
        try
        {
            var cfg = new Configuration();
            cfg.Configure();
            cfg.AddFilterDefinition(new VersionFilter());

            var types = DomainClasses(typeof(Program).Assembly, "VersionedDataModel1.Domain");

            foreach (Type type in types)
            {
                cfg.AddInputStream(HbmSerializer.Default.Serialize(type));
            }
            var sessionFactory = cfg.BuildSessionFactory();

            {
                var schema = new SchemaExport(cfg);
                schema.Drop(false, true);
                schema.Execute(false, true, false);
                //new SchemaExport(cfg).Drop(false, true);
                //new SchemaExport(cfg).Execute(false, true, false);
                //new SchemaUpdate(cfg).Execute(false, true);
            }
        }
    }
}

其中一个实体类：

[Class]
public class Store : BaseEntity
{
    private ICollection<Product> _products = new List<Product>();
    private ICollection<Employee> _staff = new List<Employee>();

    [Property(NotNull = true)]
    public virtual string Name { get; set; }

    [Set(0, Table = "ProductsInStore", Lazy = CollectionLazy.False, Cascade = "none")]
    [Key(1, Column = "StoreId")]
    [ManyToMany(2, Column = "ProductId", ClassType = typeof(Product))]
    public virtual ICollection<Product> Products { get { return _products; } set { _products = value; } }

    [Key(1, Column = "StoreId")]
    [OneToMany(2, ClassType = typeof(Employee))]
    public virtual ICollection<Employee> Staff { get { return _staff; } set { _staff = value; } }

    public virtual void AddProduct(Product product)
    {
        product.StoresStockedIn.Add(this);
        Products.Add(product);
    }

    public virtual void AddEmployee(Employee employee)
    {
        employee.Store = this;
        Staff.Add(employee);
    }
}

要查询数据，请执行以下操作：

    public IEnumerable<Product> QueryAllProducts(long? asOf)
    {
        using (var session = SessionFactory.OpenSession())
        {
            session.EnableFilter(VersionFilter.Name).SetParameter(VersionFilter.Parameter, asOf);
            return session.QueryOver<Product>().List<Product>();
        }
    }

在NHibernate调试日志中，我看到以下内容。当我构造SessionFactory时。我看到以下错误，我不确定如何解释：

2015-04-30 13:53:32,398 [1] ERROR NHibernate.Cfg.Configuration - filter-def for filter named 'VersionedDataModel1.VersionFilter, VersionedDataModel1, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' was never used to filter classes nor collections. This may result in unexpected behavior during queries

在日志中，我看到没有对过滤器的引用，也没有过滤我的Product集合。可能是我错过了这个概念。

我的想法是为整个会话应用此过滤器（VersionFilter），以便查询的所有实体都将使用此addidional WHERE ... 条件。

因此是问题 - 我对Filter / FilterDefinition缺少什么？

谢谢！

Answer 1

您已经将过滤器注册为nhibernate，现在您必须在映射类或集合中调用引用。

我从未使用属性映射，但我认为您需要使用Import-Csv -Path .\test.csv | ForEach-Object { $acct = Get-ADUser -Filter "employeeNumber -eq $($_.'Manager User Sys ID')" | select -Expand SamAccountName $_ | select *,@{Name='managerUsername';Expression={$acct}} } | Export-Csv -Path .\simpletest.csv -NoTypeInformation将过滤器与实体（类级别）相关联

或像这样的动态：

NHibernate.Mapping.Attributes.Filter

您可以在nhibernate文档中阅读更多here。

无法获得NHibernate过滤器来过滤实体 - 我是否缺少概念？

1 个答案: