在使用Fluent Nhibernate Table-Per-Subclass策略时，您可以指定标识列吗？ [英] Can you specifiy the identity column when using the Fluent Nhibernate Table-Per-Subclass strategy?

问题描述

  public class TaskDownloadMap：SubclassMap< TaskDownload> ; 
 {
 public TaskDownloadMap（）
 {
表（TasksDownload）; 
 
 Map（x => x.ExtraProperty1，ExtraProperty1）
 .Nullable（）; 
 
 Map（x => x.ExtraProperty2，ExtraProperty2）
 .Nullable（）; 
 
 
 
 
 $ b当我尝试保存这些实体时，一个例外：
 
 
  Test.TaskRepositoryTest.DeleteTest：
 NHibernate.Exceptions.GenericADOException：无法插入：[TaskManager。 （？，？，？）] 
 ----> System.Data.SqlClient.SqlException：无效的列名称Task_id。 
  
这是因为我在子类表上设置的Id列名为TaskId。有一些重写nhibernate试图使用的默认命名方案吗？我似乎没有能力在子类中指定ID列，我甚至找不到任何人谈论它。
 
 
 
父映射看起来像这样：
  public class TaskMap：ClassMap< Task> 
 {
 public TaskMap（）
 {
表（任务）; 
 
 Id（x => x.Id，Id）
 .GeneratedBy.Identity（）; 
 
。 
。 
。 
 
 
 
 
 
就像我之前说过的，使用Table-Per-Subclass策略，所以这些是2个不同的表。我可以将我的TasksDownload表上的键改为Task_id，但我宁愿只是在映射中指定它为TaskId，这样我就可以遵守命名约定。
 
解决方案
你不能用流利的API配置Subclass id，因为它是由内置的映射处理来处理的。但是你可以写一个自定义大会（带有一些额外的 acceptance ）。
样本解决方案： 
 
 
  public class JoinedSubclassIdConvention：IJoinedSubclassConvention，
 IJoinedSubclassConventionAcceptance 
 {
 public void Apply（IJoinedSubclassInstance instance）
 {
 instance.Key.Column（instance.EntityType .BaseType.Name +Id）; 
 
 $ b public void Accept（IAcceptanceCriteria< IJoinedSubclassInspector> criteria）
 {
 criteria.Expect（x => x.EntityType == typeof（TaskDownload）） ; 
 
 
 
 
 
 
 $ b然后你把你的传递添加到配置中： p> 
 
 
 流利.Configure（）
 // ... 
 .Mappings（m => 
 {
 m.FluentMappings 
 // ... 
 .Conventions.Add< JoinedSubclassIdConvention>（）; 
}）; 
  
 
I am creating a Fluent N hibernate subclass mapping that currently looks something like this:
public class TaskDownloadMap: SubclassMap<TaskDownload>
{
    public TaskDownloadMap()
    {
        Table("TasksDownload");

        Map(x => x.ExtraProperty1, "ExtraProperty1")
            .Nullable();

        Map(x => x.ExtraProperty2, "ExtraProperty2")
            .Nullable();
    }
}
When I try and save one of these entities I get an exception:
Test.TaskRepositoryTest.DeleteTest:
NHibernate.Exceptions.GenericADOException : could not insert: [TaskManager.Entities.TaskDownload#269][SQL: INSERT INTO TasksDownload (ExtraProperty1, ExtraProperty2, Task_id) VALUES (?, ?, ?)]
  ----> System.Data.SqlClient.SqlException : Invalid column name 'Task_id'.
It's because the Id column I have set on my subclass's table is named "TaskId".  Is there some to override the default naming scheme that nhibernate is trying to use?  I don't seem to have the ability to specify the "Id" column in the subclass and I can't find anyone else even talking about it.

The parent mapping looks like this:
public class TaskMap: ClassMap<Task>
{
    public TaskMap()
    {
        Table("Tasks");

        Id(x => x.Id, "Id")
            .GeneratedBy.Identity();

        .
        .
        .

    }
}
Like I said before I am going with the Table-Per-Subclass strategy so these are 2 different tables.  I can change the key on my TasksDownload table to be "Task_id" but I'd rather just be able to specify that it's "TaskId" in my mapping so I can keep to my naming convention.
解决方案
You cannot configure the Subclass id's with the fluent API because it's handled by the built in mapping convetions. But you can write a custom convention (with some extra acceptance if required).

A sample solution:
public class JoinedSubclassIdConvention : IJoinedSubclassConvention, 
     IJoinedSubclassConventionAcceptance
{
    public void Apply(IJoinedSubclassInstance instance)
    {
         instance.Key.Column(instance.EntityType.BaseType.Name + "Id");
    }

    public void Accept(IAcceptanceCriteria<IJoinedSubclassInspector> criteria)
    {
        criteria.Expect(x => x.EntityType == typeof(TaskDownload));
    }
}
Then you add your convetion to the configuration:
Fluently.Configure()
    //...
    .Mappings(m =>
        {
            m.FluentMappings
            //...
            .Conventions.Add<JoinedSubclassIdConvention>();
        });


                        
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